Switching On And Power-On Conditions; Output Control; Constant Current; Operation - Thurlby Thandar Instruments New PL Serie Manual Del Usuario

In this manual front panel keys, controls and sockets are shown in capitals, e.g. CURRENT,
OUTPUT, LOCK. Messages displayed on the 7-segment LEDs are shown in a different type-font,
e.g. turn oFF, OtP trip. The additional features of the Quad-mode Dual instrument are
described together at the end of this chapter.

Switching On and Power-On Conditions

The POWER switch is located at the bottom left of the front panel. When the POWER switch is
l
turned on ( ) the right hand meter briefly indicates the firmware revision before the display
shows Volts and Amps.
At power on, the factory default setting is for the output to be off. All other settings will be the
same as they were at last power off.
Repeating the procedure will change the setting back to the previous state. Note that the power-
on status of the two outputs of the dual supply need to be set individually.

Output Control

Setting Up the Output
With the POWER switch on and the
accurately preset using the VOLTAGE and CURRENT controls; the left-hand meter shows the set
voltage, the right-hand meter shows the set maximum current and the SETTINGS indicator is lit.
When the output switch is switched on, the OUTPUT indicator lights; the left-hand meter now
shows the actual voltage and the right-hand meter the actual load current.
To change the current limit range the output must be switched off; if the output is on the warning
message turn oFF
range remains unchanged.
Constant Voltage
The output voltage is adjusted using the main and fine VOLTAGE controls; the CURRENT control
sets the maximum current that can be supplied.

Constant Current

If the load resistance is low enough such that, at the output voltage set, a current greater than the
current limit setting would flow, the power supply will automatically move into constant current
operation. The current output is adjusted by the CURRENT control and the VOLTAGE controls
set the maximum voltage that can be generated.
The CC indicator lights to show constant current mode.
The dc output state at power-on can be set to be 'always off' or 'same as
at last power-off'. The setting can be changed as follows. With the VIEW
key held down, press and hold down the
will first show the present setting for 1 second (
default is still selected) before flashing the new setting for 2 seconds (
LASt Set in this instance). After 2 seconds the new setting is shown
continuously in the display and the change is implemented; release the
OUTPUT and VIEW keys.
OUTPUT off the output voltage and current limit can be
The upper limit of the CURRENT control can be switched
between the maximum for this model and 500mA with
alternate presses of the 500mA RANGE key to give finer
current limit setting and measurement resolution (0.1mA up to
500mA); the indicator beside the key is lit when the 500mA
range is selected.
is shown briefly in the display, the OUTPUT indicator flashes and the

Operation

OUTPUT key; the display
OP OFF if the factory
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