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EPP-601 Fuente de alimentación de plasma Manual de instrucciones - ES 0558007982 06/2012...
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Si usted no entiende completamente estas instrucciones, entre en contacto con a su distribuidor ESAB para información adicio- nal. Asegure leer las medidas de seguridad antes de instalar o de operar este equipo.
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3.6.1 Conexiones para dos EPP-601 en paralelo ........
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ÍNDICE Apartado / Título Página Localización y resolución de problemas ............. . .35 6.1 General.
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PRECAUCIONES DE SEGURIDAD Precauciones de seguridad Los usuarios de los equipos de corte y soldadura ESAB tienen la responsabilidad de asegurar que las personas que trabajan o están cerca del equipo sigan las normas de seguridad. Las precauciones de seguridad deben estar de acuerdo con equipos de corte y soldadura. Las recomendaciones abajo deben ser seguidas adicionalmente a las normas estándar.
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Proteja sus oídos. utilice protección auricular. Avise las personas al rededor sobre el riesgo. AVERÍAS – Llame a ESAB en caso de una avería con el equipo. LEER Y ENTENDER EL MANUAL ANTES DE INSTALAR U OPERAR EL EQUIPO. PROTEJA A USTED Y LOS OTROS! Este producto está...
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La fuente de alimentación EPP está diseñada para aplicaciones de marcado y de corte mecanizadas de plasma de alta velocidad. Puede utilizarse con otros productos de ESAB como los sopletes PT-15, PT-19XLS, PT-600 y PT-36 además de con el Smart Flow II, un sistema computerizado de conmutación y regulación de gas.
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APARTADO 2 DESCRIPCIÓN Dimensiones y peso 1143 mm 946 mm 45.00” 37.25” 1022 mm 40.25” Peso = 850 kg. (1870 libras)
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Prevea el hecho de que los paneles superior y laterales puedan tener que retirarse para mantenimiento, limpieza e inspección. • Ubique el EPP-601 relativamente cerca de una fuente de alimentación eléctrica con los fusibles adecuados. • Mantenga una zona libre debajo de la fuente de alimentación para permitir el flujo de aire de refrigeración.
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LÍNEA DE LA PARED PARA CORTAR LA CORRIENTE. 3.4.1 Alimentación principal EPP-601 es una unidad trifásica. La alimentación de entrada debe proporcionarse desde un conmutador de desconexión de línea (de pared) que contenga los fusibles o disruptores de circuito conforme a las normas locales.
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AVISO anillo. Los conductores de entrada deben terminar en terminales de anillo de un tamaño de 12,7 mm antes de que se unan al EPP-601. Inspeccione el espacio entre los terminales de anillo principales de alimentación y el panel lateral. Los cilindros de algunos terminales...
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APARTADO 3 INSTALACIÓN ¡LAS DESCARGAS ELÉCTRICAS PUEDEN MATAR! LOS TERMINALES EN ANILLO DEBEN MANTENER UN ESPACIO ENTRE EL PANEL LATERAL Y EL TRANSFORMADOR PRINCIPAL. ADVERTENCIA EL ESPACIO DEBE SER SUFICIENTEMENTE GRANDE COMO PARA EVITAR UN POSIBLE ARCO ELÉCTRICO. ASEGÚRESE DE QUE LOS CABLES NO INTERFIERAN CON LA ROTACIÓN DEL VENTILADOR DE REFRIGERACIÓN.
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(generador alta frec.) 3.6 Instalación paralela Se pueden conectar dos EPP-601 fuentes de alimentación en paralelo para ampliar el rango de salida de corriente. Utilice solamente una fuente de alimentación para cortar por debajo de 100A.
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[corriente de salida (amperios)] = [voltaje de referencia] x [160] en el rango de alta corriente El EPP-601 no tiene un conmutador de conexión/desconexión. La alimentación principal se controla mediante el conmu- tador de desconexión de línea (de pared).
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(generador alta frec.) (generador alta frec.) Las conexiones de la instalación en paralelo de las dos fuentes de alimentación EPP-601 con sólo una fuente de alimentación en funcionamiento. Las conexiones que se detallan a continuación son adecuadas para un funcionamiento en paralelo de hasta 600A al 100% del ciclo de servicio.
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3.6.2 Marcado con dos EPP-601 en paralelo Dos EPP-601 conectadas en paralelo pueden utilizarse para marcar a 20 A y para cortar de 100 A a 1000 A. Se pueden llevar a cabo dos modificaciones sencillas en la fuente de alimentación suplementaria para permitir un marcado de 10A. Las modificaciones sólo son necesarias si es necesario un marcado por debajo de 20A.
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APARTADO 3 INSTALACIÓN 3.7 Cables de interfaz Interfaz CNC (24 conductores) Interfaz de refrigeración de agua (8 conductores) 3.7.1 Cables de interfaz CNC con el conector de la fuente de alimentación unido e Interfaz CNC sin término Conector macho P/N: 647032 GRN/YEL RED #4...
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APARTADO 3 INSTALACIÓN 3.7.2 Cables de interfaz CNC con el conector de la fuente de alimentación unido e interfaz CNC sin término Conector macho Conector CNC P/N: 647032 P/N: 2010549 GRN/YEL RED #4 3.7.3 Cables de interfaz de refrigeración de agua con los conectores de fuente de alimentación unidos por ambos extremos Conector hembra Conector macho...
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APARTADO 4 FUNCIONAMIENTO 4.1 Descripción del circuito de diagrama de bloque...
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útil del soplete normalmente se mejora con una ondulación baja. El gráfico a continuación muestra el efecto de la reducción de la ondulación patentada por ESAB mediante dos reductores sincronizados y conmutado de manera alterna. En comparación con dos reductores que funcionen simultáneamente, la conmutación alterna normalmente reduce la ondulación en un factor de 4 a 10.
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4.1 Descripción del circuito de diagrama de bloque (continuación) El diagrama de bloque de EPP-601 (según el subapartado 4.1) muestra los principales elementos funcionales de la fuente de alimentación. T1, el transformador principal, proporciona aislamiento de la línea de alimentación principal, así como el voltaje correcto para el bus *375 V DC.
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F - Dial de corriente (potenciómetro) Se muestra el dial del EPP-601. EPP-601 tiene un rango de 10A a 100A en el rango de corriente bajo y de 50A a 600A en el rango de corriente alto. El potenciómetro se utiliza solamente en modo de panel.
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BAJO. Esto puede variar dependiendo del gas, el material y el soplete utilizado. Las configuraciones alto/bajo se especifican en los datos de corte incluidos en el manual del soplete. Cuando la EPP-601 está configurada en el modelo de marcado, este conmutador debe colocarse en la posición de bajo.
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APARTADO 4 FUNCIONAMIENTO 4.2 Panel de control (continuación) J - Medidores Muestra el voltaje y el amperaje durante el corte. El amperímetro puede activarse con el conmutador actual/preconfiguración cuando no se esté cortando para ver una estimación de la corriente de corte antes de que comience el corte. K - Conmutador de actual/preconfiguración El conmutador con resorte de vuelta AMPERIOS ACTUAL/AMPERIOS PRECON- FIGURACIÓN, S4, se encuentra por defecto en la posición ACTUAL (ARRIBA).
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4.2.1 Modos de funcionamiento: Modos de corte alto y bajo y modo de marcado El EPP-601 funciona en el modo de corte en dos rangos de corriente. El rango de corriente bajo es de 35-100A correspondiente a una señal V de 3,50 V-10,00 V.
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Operation 4.3 Sequence of Operation Aplique energía cerrando el conmutador de línea (de pared). (El EPP-601 no tiene un conmutador de conexión/desco- nexión). La luz de alimentación principal se iluminará y la luz de fallo parpadeará y después se apagará.
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El tiempo para alcanzar la corriente completa puede ajustarse para un arranque suave. Esta característica utiliza una corriente reducida para arrancar y después gradualmente va aumentando hasta alcanzar una corriente completa. El EPP-601 se envía de fábrica con el arranque suave activado. La configuración por defecto es la siguiente: Corriente de arranque mínima .
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APARTADO 4 FUNCIONAMIENTO 4.4.1 Activación/Desactivación de las condiciones de iniciación del arco La configuración de fábrica por defecto es la siguiente: Conectado Desconectado 1. Retire el panel de acceso en la esquina superior derecha del parte frontal. Asegúrese de recolocar este panel después de hacer los ajustes.
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APARTADO 4 FUNCIONAMIENTO 4.4.4 Controles de iniciación del arco Potenciómetro de corriente de arranque Temporizador de subida 4.4.5 Corriente de arranque y temporizador de subida Relación entre la corriente de arranque (%) y Corriente de arranque la configuración de potencia Configurada mediante el potenciómetro ubicado encima, a la izquierda del centro de PCB1.
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APARTADO 4 FUNCIONAMIENTO 4.5.1 Curvas aproximadas V-I EPP-601 para todos los modelos Voltaje de salida (Voltios) = 1,00V Mínimo Rango bajo de marcado = 0,625 V Corriente de rango alto mínima = 1,000 V Rango alto = 10,00 V Máximo. Rango bajo...
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section 5 maintenance 5.1 General electric shock can kill! warninG shut off power at the line (wall) disconnect before at- temptinG any maintenance. eye hazard when usinG compressed air to clean. warninG • Wear approved eye protection with side shields when cleaning the power source.
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5 maintenance air restrictions may cause epp-601 to over heat. thermal switches may be activated causing interruption of func- caution tion. do not use air filters on this unit. keep air passages clear of dust and other obstructions. 5.3 lubrication •...
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section 6 troubleshootinG 6.1 General electric shock can kill! warninG do not permit untrained persons to inspect or repair this equipment. electrical work must be performed by an expe- rienced electrician. stop work immediately if power source does not work properly. caution have only trained personnel investigate the cause.
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section 6 troubleshootinG Fault Indicator (Front Panel) Illuminates when there are abnormalities in the cutting process or when the input voltage falls ±10% outside the normal value. Momentary illumination is normal. If continuously lit, check LEDs 3, 4, 5, 7, and 8 on PCB1 for further diagnosis. LED 3 – (yellow) Bus Ripple Fault - Momentarily illuminates at the beginning of each cut. Continuously lit during single-phasing or imbalanced line-to-line voltages of the three phase input line (Excessive Ripple). Power Source is shut down. LED 4 – (yellow) High Bus Fault – Illuminates when input line voltage is too high for proper operation (approximately 20% above nominal line voltage rating). Power source is shut down. LED 5 – (yellow) Low Bus Fault – Illuminates when input line voltage is lower than 10% below nominal line voltage rating. Power Source is shut down. LED 7 – (yellow) Arc Voltage Saturation Fault – Illuminates when the cutting arc voltage is too high and cutting current drops below preset level. LED will extinguish after voltage decreases and current rises. LED 8 – (yellow) A rc V oltage C utoff F ault – Illuminates w hen a rc voltage increases over the preset value. PS is shut down.
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section 6 troubleshootinG Power Reset Fault Indicator (on front panel) Illuminates when a serious fault is detected. Input power must be disconnected for a least 5 seconds to clear this fault. Check PCB1 Red LEDs 6, 9, 10, 11, 12, and 13 if this fault is illuminated for further diagnosis. LED 6 – (red) Right Overcurrent Fault – Illuminates when the current out of the right side chopper is too high (400 amps). This current is measured by the right-side hall sensor. The power source is shut down. LED 9 – (red) Left Overcurrent Fault – Illuminates when the current from the left side chopper is too high (400 amps). Measured by the left hall sensor. Power source is shut down. LED 10 _ (red) Left IGBT Unsaturated Fault – Illuminates when left IGBT is not fully conducting. PS (PS) is shut down. LED 11 – (red) Right IGBT Unsaturated Fault – Illuminates when right IGBT is not fully conducting. Power Source (PS) is shut down. LED 12 – (red) Left -(neg) 12V Bias Supply Fault – Illuminates when negative 12 V bias supply to the left side IGBT gate drive circuit (located on PWM-drive board PCB2) is missing. PS is shut down. LED 13 – (red) Right –(neg) 12V Bias Supply Fault - Illuminates when negative 12 V bias supply to the right side IGBT gate drive circuit (located on PWM drive board PCB3) is missing. PS is shut down.
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section 6 troubleshootinG 6.3 fault isolation Many of the most common problems are listed by symptom. 6.3.1 No output with contactor signal applied 6.3.2 Output limited to 100A 6.3.3 Fans not working 6.3.4 Power not on or low voltage 6.3.5 Fault light illumination 6.3.6 Torch won’t fire 6.3.7 Fusses blown - F1 and F2 6.3.8 Intermittent, interrupted or partial operation 6.3.1 no output with contactor signal applied problem possible cause action External emergency stop (E-stop) is Connect isolated contact of E-stop switch to pro- open.
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section 6 troubleshootinG 6.3.4 power not on or low voltage problem possible cause action Restore all 3 phases of input voltage to within Missing 3-phase input voltage ±10% of nominal line. Power source inoperable: Main power lamp is off. Restore all 3 phases of input voltage to within Missing 1 of 3-phase input voltage ±10% of nominal line. Fuse F3/F4 blown Replace F3/F4 Low open circuit voltage Pilot arc Contactor (K4) faulty Replace K4...
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section 6 troubleshootinG problem possible cause action Cutting at over 400A with a faulty left side See faulty left or right side (left side output = 0) Right current transducer connector loose Secure connections or unplugged. PCB loose. LED 6 – (red) Right Over Cur- Loose or unplugged connector at right Secure connection rent PWM/Drive Printed circuit board. P2 at left of PWM / Drive PCB loose or un- Secure connection plugged. note: Check voltage between P7-6 and P7-7. A If operation at 400A or less is voltage in either polarity of greater than Replace right current transducer possible, then the LEFT side is 0.01 V indicates a faulty right current trans-...
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section 6 troubleshootinG problem possible cause action Shorted IGBT Replace the IGBTs Current pot set too high Lower the current setting Very high Output current ac- companied by either a left or Faulty left PWM / Drive PCB Replace left PWM / Drive PCB right over current (LED 6) High remote current signal Decrease remote current signal Faulty PCB1 Replace PCB1 P/N 0558038313 Black wire connecting IGBT (Q2) collector to P3 of the Secure connector left PWM / Drive PCB (PCB2) is disconnected. Shorted Freewheeling Diode(s) Replace freewheeling diode(s) Loose or unplugged P1 connector at the left PWM / LED 10 - (red) Left IGBT Un- Secure P1 Drive PCB saturated Loose or unplugged P10 connector at PCB1 Secure P10 Faulty PCB1 Replace PCB1 P/N 0558038313 Faulty left PWM / Drive PCB Replace PCB2 P/N 0558038324 Black wire connecting IGBT (Q5) collector to P3 of the Secure connector right PWM / Drive PCB (PCB3) is disconnected. Shorted Freewheeling Diode(s) Replace freewheeling diode(s) Loose or unplugged P1 connector at the left PWM / LED 11 - (red) Right IGBT...
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section 6 troubleshootinG problem possible cause action Loose or unplugged P1 connector at Secure P1 connector the left PWM / Drive PCB Loose or unplugged P10 connector LED 12 – (red) Left –12V Missing Secure P10 connector at PCB1 Replace left PWM / Drive PCB P/N Faulty left PWM / Drive PCB 0558038324 Loose or unplugged P1 connector at Secure P1 connector the right PWM / Drive PCB Loose or unplugged P11 connector LED 12 – (red) Right –12V Missing Secure P11 connector at PCB1 Replace right PWM / Drive PCB P/N Faulty right PWM / Drive PCB 0558038324 Shorted IGBT...
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section 6 troubleshootinG 6.3.6 torch will not fire problem possible cause action Remote control removes the start signal when the main arc transfers to the work. Place Panel/Remote switch in “Panel” position Panel/Remote switch in “Remote” with no remote control of the current Main Arc Transfers to the work with a Check f or c urrent r eference s ignal a t T B1- short “...
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section 6 troubleshootinG 6.3.7 fuses f1 and f2 blown problem possible cause action Process controller must allow at least Process controller ignites pilot arc too 300MS to lapse between the applica- soon after providing the “Contactor tion of the “Contactor On” signal and On” signal the ignition of the pilot arc. Fix process controller logic and replace diodes. Faulty negative (Electrode) output cable Repair cable shorting to earth ground.
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section 6 troubleshootinG problem possible cause action Power source is OK. Trouble shoot pro- “Contactor On” signal is removed from unit. cess controller. Restore and maintain input voltage Momentary loss of primary input power. within ±10% of nominal. Remove control PCB (PCB1) access panel Faulty condition, indicated by illumination to determine the fault causing the shut- of the fault lamp. down. Refer to fault light illumination Power Supply turns off prema- section. turely in the middle of the cut. Remove control PCB (PCB1) access panel Faulty c ondition, i ndicated b y t he i llumination to determine the fault causing the shut- of the power reset fault lamp.
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6 troubleshootinG 6.4 testing and replacing components • Replace a PC board only when a problem is isolated to that board. • Always disconnect power before removing or installing a PC board. • Do not grasp or pull on board components. notice • Always place a removed board on a static free surface. • If a PC board is found to be a problem, check with your ESAB distributor for a replacement. Provide the distributor with the part number of the board as well as the serial number of the power source. • Do not attempt to repair the board yourself. Warranty will be voided if repaired by the customer or an unauthorized repair shop. power semiconductor components Categories of power semiconductors include; • Power Rectifiers • Modules containing the free wheeling diodes and IGBTs...
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section 6 troubleshootinG 6.4.1 power rectifiers and blocking diodes Power Rectifiers Power Rectifiers Procedure to access behind the front panel 1. Remove top cover and side panels 2. Locate and disconnect plug in rear of ammeter (attached tone red and one black wire) 3. Remove pilot arc switch 4. Disconnect voltmeter 5. Disconnect orange and yellow wires from relay K4. 6. Remove two bolts holding the left side of the front panel to the base. 7. Remove three bolts holding across the center base of the front panel. These are accessed from underneath. 8. Remove one of the bolts holding the right side of the front panel to the base. Loosen the second bolt. Of these two bolts, remove the bolt on the left and loosen the bold on the right.
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section 6 troubleshootinG NEG Plate Diode Rectifier 1. Check ohms between NEG Plate and BR “ A” Bus. A reading of 2 ohms or less indicates one or more shorted diodes. Replace all Diodes on NEG Plate. 2. If fuses F8 and/or F9 were open in the first step, make two more ohmmeter readings. A. Measure resistance between the NEG Plate and BR “B” bus. Electrode Plate POS Plate B. Measure between NEG Plate and BR “C” bus. If resistance is 2 ohms or less in either case, replace all the diodes on the NEG Plate. troubleshooting pos plate 1. Check ohms between POS Plate and BR “ A” Bus. A reading Location of Pos. Plate of 2 ohms or less indicates one or more shorted diodes.
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section 6 troubleshootinG 6.4.2 iGbt / freewheeling diode (fwd) replacement the emitter and the gate of each affected iGbt must be jum- caution pered together to prevent electrostatic damage. each power source is supplied with six jumper plugs that mate to the iGbt Gate / emitter plug.
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section 6 troubleshootinG replacement: A. Thoroughly clean any thermal compound from the heat sink and the modules. Any foreign material trapped between the module and heat sink, other than an appropriate thermal interface, can cause module damage due to over heat- ing. B. Inspect the thermal (interface) pad, P/N 951833, for damage. A crease or deformity can prevent the module from seat- ing properly, impeding the heat transfer from the module to the heat sink. The result can be module damage due to over heating. If a thermal pad is not available, a heat sink compound such as Dow Corning® 340 Heat Sink Compound may be used. It’s a good idea to mount all paralleled modules located on the same heat sink using the same thermal interface. Different in- terfaces can cause the modules to operate at different temperatures resulting in un-equal current sharing. The imbalance can shorten module life. C. Place a thermal pad, and an IGBT module on the heat sink. Carefully align the holes in the thermal pad with the heat- sink and module holes. If heat sink compound is used in place of a thermal pad, apply a thin coat of even thickness to the metal bottom of the module. A thickness of 0.002” – 0.003” (0.050mm – 0.075mm) is optimum. Too much com- pound impedes heat transfer from the module to the heat sink resulting in short module life due to over heating. D. Insert the four M6 mounting bolts, but do not tighten. Leave them loose a few turns. Be certain that the threads from the mounting bolts do not bend the edges of the thermal pad clearance holes. A bent thermal pad can prevent the module from seating properly, impeding the heat transfer from the module to the heat sink. The result can be module damage due to over heating. E. Partially tighten the four mounting bolts a little more than finger tight in the order: A-B-C-D. See figure below. F. Fully tighten, in the same order above, to a torque of 35 – 44 in-lbs (4.0 – 5.0 N-M). See figure below. G. Install the bus plates and bus bars. Be careful that the sheets of insulation separating the bus plates are still in their original positions. It’s a good idea to tighten the mounting hardware only after getting it all started. Torque the M6 module terminal hardware to 35 – 44 in-lbs (4.0 – 5.0 N-M). H. Remove the jumper plugs from the module gate lead plugs, and plug into the appropriate plugs from the PWM/Gate Drive PC Board. See Caution below. Replace the top panel. the module gate plugs must be plugged into the pwm/Gate caution drive pc board whenever the power source is in operation.
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section 6 troubleshootinG 6.4.3 power shunt installation instability or oscillation in cutting current can be caused by im- caution proper dressing of shunt pick-up leads. poor torch consumable life will be the result. There are two cables that attach to the shunt pick-up points: a two conductor cable drives the ammeter a three conductor which provides the current feedback signal to PCB1 (control PCB). Dressing of the 2 conductor cable is not critical. The following is the dressing procedure for the 3 conductor cable. • The breakout point should be physically at the middle of the shunt. The breakout point is the place where the conductors exit from the outer insulation jacket.
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2. Compare the power source voltmeter reading to the calibrated meter reading. Readings should match within ±0.75%. Ammeter 1. External to the power source, connect a precision shunt in series with the work lead(s). The best shunt is one with a value of 100 micro-ohms (50mV / 500A or 100mV / 1000A) and a calibrated tolerance of 0.25%. 2. Use a calibrated 4 ½ digit meter to measure the output of the shunt. The amperage indicated with the external shunt and meter should match power source ammeter to within 0.75%. 6.5 control circuit interface using J1, J4 and J6 connectors Interface to the EPP-601 control circuitry is made with connectors J1, J4 and J6 on the front panel. J1 has 24 conductors, J4 has 2 and J6 has 10. J1-P and J1-G provide access to the galvanically isolated transistor output signal indicating an “Arc On” condition. See Subsection 6.8, Arc Current Detector Circuits. J1-L and J1-J are the inputs for the remote Voltage Reference Signal that commands the EPP-601 output current Subsection 6.9, Current Control Pot & Remote Vref. J1-R and J1-Z supply 115V AC for remote controls. See Subsection 6.6, Auxiliary Main Contactor (K3 and K33) & Solid State Contactor Circuits and Subsection 6.10, Pilot Arc Hi/lo & Cut/mark Circuits. J1-E and J1-F are the input connections for the Emergency Stop function. For Emergency Stop to operate, the Jumper between TB8-18 and TB8-19 must be removed.
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6 troubleshootinG CONTROL CIRCUIT INTERFACE USING J1, J4, & J6 CONNECTORS EPP-450 POWER SOURCE epp-601 power source CONTROL J4-A ISOLATED CONTACT J4-B E-STOP BUTTON E-STOP RELAY REMOTE EMERGENCY STOP TB8-19 J1-F RED 06 ISOLATED CONTACT J1-E 24 VAC E-STOP LOOP MUST BE...
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section 6 troubleshootinG 6.6 auxiliary main contactor (k3 & k33) and solid state contactor circuits K3 and K33, activated by supplying a Contactor Signal, initiate and controls the operation of K2 (Starting Contactor) and K4 (Pilot Arc Contactor). K3/K33 are called the Auxiliary Main Contactors because they must be activated before the Main Contactor (K1) power-up sequence can occur. The Contactor Signal is supplied through a remote contact connect- ing 115VAC from J1-R to J1-M. If K6 is closed (no fault), K3 will activate. The closing of K3(6, 9) activates K2, the Starting Contactor, and K4, the Pilot Arc Contactor, provided the power source is not over heated. See Subsection 6.7, E-stop and Main Contactor Circuits for more information on the operation of K2. K4 is turned off when the Current Detector senses arc current and opens the contact connecting P2-5 to P2-6 on the Control PC Board. In addition to operating K3/K33, the Contactor Signal also activates the Solid State Contactor. The Solid State Contactor is a logic and interlock circuit permitting the IGBT’s to conduct whenever the remote Contactor Signal is present. The 115V AC Contactor Signal is fed to TB1-9, TB7-8, and resistors R45 and R45-A. These resistors reduce the 115V to approximately...
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section 6 troubleshootinG 6.7 e-stop (emergency stop) and main contactor (k1a, k1b and k1c) circuits A power-up sequence takes place before the Main Contactor (K1) activates. K1 is actually three separate contactors – one for each primary input phase. Thus, K1A, K1B, and K1C switch phases A, B, and C respectively to the Main Transformer, T1. The power-up sequence begins with a remote Contactor Signal activating K3 and K33. Refer to the description entitled, Section 6.6, Auxiliary Main Contactor (K3 and K33) & Solid State Contactor Circuits for more information. K3 and K33 acti- vates K2 closing the three contacts of K2. K2 bypasses K1 contacts providing primary input power to the Main Transformer, T1. This current is limited by three one Ohm resistors, R1, R2, and R3. The resistors eliminate the high surge currents typical of the turn-on inrush transients associated with large transformers. The high current surge of charging the Bus Capacitor Bank is also eliminated by initially powering the Main Transformer through K2 and the resistors. The discharged Bus Capacitor Bank initially prevents the output of the Main transformer from reaching its normal value. As the Bus Capacitor Bank charges, the Main Transformer output voltage rises and becomes high enough for K1A, K1B, and K1C to close. Once the K1’s are closed, the contacts of the Starting Contactor, K2, are bypassed, and full primary line power is supplied to the Main Transformer through the contacts of the K1’s. Because the starting sequence takes time, it is important at least 300 mS lapse between applying the Contactor Signal and applying load to the power source. Applying load too soon will prevent the K1’s from closing and fuses F1 and F2 will open. K15, the E-Stop relay must be closed for the power-up sequence to take place. K15 contains one contact in the K2 coil circuit and another contact in the K1A, K1B, & K1C circuits. There is no power supplied to the Main Transformer, T1, until K15 is acti- vated. For K15 to activate, S5, the E-Stop switch on the front panel must be closed. Also, the Plasma Control must complete the E-stop loop by closing an isolated contact between J1-E and J1-F. The E-Stop switch is closed whenever the E-Stop button, on the front panel, is pulled out. For troubleshooting purposes only, a jumper can be connected between TB8-18 and TB8-19. If a jumper is installed, it MUST be removed before placing the power source back into service. If the jumper is not removed, the power source E-Stop condition will not function when the E-Stop button for the Plasma Control is pushed. J4-A and J4-B are connected together whenever the E-Stop button on the power source is pulled out. This signal can be sent to the Plasma Control so that the control senses the state of the power source E-Stop switch.
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section 6 troubleshootinG 6.7 e-stop (emergency stop) and main contactor (k1a, k1b and k1c) circuits (continued)
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6 troubleshootinG 6.8 arc current detector circuits There are three Arc Current Detector circuits in the EPP-601. One is used internally to control the Pilot Arc Contactor, K4. The other two are available for remote use. A galvanically isolated transistor Current Detector Output is accessible at J1-G (-) and J1-P (+). J1 is the 24 conductor con- nector on the EPP-601 front panel. The transistor is best suited for switching small relays or low current logic signals like those utilized by PLC’s (Programmable Logic Controllers). The transistor can withstand a maximum peak voltage of 150V. It can switch a maximum of 50 mA. The transistor turns on whenever the arc current through the Work Lead exceeds 5A. Pilot arcs not establishing main arcs will not turn on the transistor. A second current detector output is available at TB8-3 and TB8-4. This output is supplied by an isolated relay contact rated for 150V, 5 Amperes. This contact is closed when the primary input power to the EPP-601 is off. It opens whenever primary power is supplied to the power source, and it closes when main arc current is established. Like the transistor output, the relay contact closes whenever the arc current through the Work Lead exceeds 5A. Pilot arcs not establishing main arcs will not close the contact. J6-D J6-E J1-G J1-P...
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6 troubleshootinG 6.9 current control pot and remote vref A Reference Voltage, V , is used to command the output current of the EPP-601. V is a DC voltage that can come from either the Current Control Potentiometer on the front panel or from a remote source. In the “Panel” position, S2, the Panel / Remote switch selects the Current Control Potentiometer. In the “Remote” position, the Panel/Remote switch selects the fed into J1-L (+) and J1-J (-). The EPP-601 Output Current, I , will follow V with the following relationship: = (80) x (V ) in the high output current mode and I = (10) x (V ) in the low output current mode. PCB10 is the analog signal scaling board. If 115VAC is fed into P1-2 and P1-3 the output current range is in the high mode used for cutting from 50 to 600A. With the 115VAC absent, the output current range is in the low mode used for marking between 10 and 100A and cutting between 35 and 100A. The Control PC Board contains two inputs for V : High Speed; and Normal. When the negative of the V signal is fed into the High Speed input (P8-3), the EPP-601 will respond to a change in V within 10 mS. When the negative of the V signal is fed into the Low Speed input (P8-1), the EPP-601 will respond to a change in V within 50 mS. The slower response of the “Normal” input helps filter electrical noise sometimes encountered in industrial environments. CONTROL 0.00-10.00V CURRENT REFERENCE EPP-600: I(out) = (80) X Vref...
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6 troubleshootinG 6.10 high / low cut current modes and mark mode A remote contact connecting 115V AC from J1-R to J1-S places the Pilot Arc in High by operating K8. Note, that for this func- tion to operate, the Pilot Arc Hi/Lo switch on the front panel must be in the “LO” position. The EPP-601 is placed in the Marking mode when a remote contact connecting 115V AC from J1-R to J1-C operates K11. In the Marking mode, a normally closed contact on K11 opens turning off K10. When K10 turns off, the Boost supply is discon- nected lowering the normal Cutting Mode 430V DC Open Circuit Voltage to 360VDC for Marking. A normally open contact on K11 activates K12. K12 connects the I (min) resistors necessary for stabilizing the low currents required for marking. In the Cutting mode, the minimum stable output current is 50A in the high current range, 35A in the low current range and 10A in the marking mode. In the marking mode, the normally closed contacts K11(3, 9) and K11(1, 7) open. This deactivates HIGH/LOW CUT CURRENT MODES & MARK MODE K13 and K14 placing the power source in the low current range. Z BIAS PCB3 Right PWM/Gate Drive P5-3 P5-2 P5-1 SEE PAGE 2...
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6 troubleshootinG 6.11 low current range The EPP-601 operates in either LOW or HIGH current output ranges. The LOW range is used for marking from 10 to 100 amperes and cutting from 35 to 100 amperes. The HIGH range is used for cutting from 50 to 450 amperes. In the HIGH range, both the left and right power sources are used. Each side contributes 50% of the total output current. The left side acts as a master power source by synchronizing the switching of the right side to its own switching frequency of 10 KHz. In the LOW range, only the left power source is used. The normally open contact, K13(6, 9) prevents T7 from supplying bias supply power to PCB-3, the right PWM / IGBT Gate Drive PC Board. This disables the right side. The same K13 contact (square labeled “D” on the schematic diagrams) places the EPP-601 in the HIGH current mode. In addition to providing bias power to PCB-3 in the HIGH current mode, this 115 VAC is fed into PCB-10 P1-2. PCB-10 performs two functions. With no input on PCB-10 P1-2, PCB-10 scales the 0 to 10 VDC current reference signal for 0 to 100 amperes (LOW range). In the LOW range, PCB-10 P4-11 / P4-12 provides a signal to PCB-2 P4-1 / P4-2. This signal com- mands PCB-2, the left (master) PWM / IGBT Gate Drive PC Board to change the switching frequency from 10 KHz to 25 KHz. The higher switching frequency results in the more power dissipation by the heat sinks on PCB-3. Therefore, in the LOW current mode, a small fan, M5, turns on to provide additional cooling. M5 does not operate in the HIGH current mode. 6.12 electrode current transducer circuit The Electrode Current Transducer Circuit provides a galvanically isolated signal to the plasma control indicating the power source output current. The scaling of the signal is: VOUT = IELECTRODE/100. For example, 200A results in 2.0V output. The scaling is the same for both high and low current ranges. The output signal resistance is 100 Ohms. PCB11 receives the signal from the Hall Effect Transducer and sends the signal through FN5 to J1-Y (+) and J1-J (-). PCB11 sup- plies +15V and -15V to operate the transducer. It also buffers the signal to prevent damage to the transducer from voltage ELECTRODE CURRENT TRANSDUCER CIRCUIT transients generated outside the power source. J1-Y J1-J & TB1-5, DC...
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7 replacement parts replacement parts General Always provide the serial number of the unit on which the parts will be used. The serial number is stamped on the unit serial number plate. ordering To ensure proper operation, it is recommended that only genuine ESAB parts and products be used with this equipment. The use of non-ESAB parts may void your warranty. Replacement parts may be ordered from your ESAB Distributor. Be sure to indicate any special shipping instructions when ordering replacement parts. Refer to the Communications Guide located on the back page of this manual for a list of customer service phone numbers. epp-601 input/output information epp-601 epp-601 epp-601 epp-601 epp-601 380v 50/60hz 380v 50/60hz 400v 50/60hz 460v 60hz 575v 60hz part number 380v taps 400v taps...
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1. Original release - 02/2008 2. 05/2008 - added E-stop information throughout manual. Included Replacement Parts section in Schematic / Wiring Diagram package. Changed power supply name from EPP-600 to EPP-601. 3. Revision 08/2010 - Updated with new DOC form. 4. Revision 06/2012 - dimensions changes section 2.3.