Maintenance - TTI EX355R Manual De Instrucciones

Series or Parallel Connection with Other Outputs
The outputs of the power supply are fully floating and may be used in series with other power
supply units to generate high DC voltages up to 300V DC.
The maximum permissible voltage between any terminal and earth ground (
WARNING! Such voltages are exceedingly hazardous and great care should be taken to shield
the output terminals for such use. On no account should the output terminals be touched when
the unit is switched on under such use. All connections to the terminals must be made with the
power switched off on all units.
It should be noted that the unit can only source current and cannot sink it, thus units cannot be
series connected in anti-phase.
The unit can be connected in parallel with others to produce higher currents. Where several units
are connected in parallel, the output voltage will be equal to that of the unit with the highest output
voltage setting until the current drawn exceeds its current limit setting, upon which the output will
fall to that of the next highest setting, and so on. In constant current mode, units can be
connected in parallel to provide a current equal to the sum of the current limit settings.
Note that the output terminals are rated at 15A maximum; if several outputs are operated in
parallel to source higher currents than this the junction should be made at a separate point, not
one of the terminals.
Ventilation
The power supply is very efficient but nevertheless can generate significant heat at full power.
The supply relies on convection cooling only and it is therefore important that ventilation is never
restricted if performance and safety are to be maintained.
Audible Noise
When the DC output power is reduced to a few Watts at low voltages and/or low current levels the
switched−mode stage controller starts to 'skip' pulses. This has the effect of bringing the
switching frequency into the audio range and occasionally some audible noise can be heard
because of the electro−acoustic action of the transformer. This is entirely normal and does not
affect performance in any way.
The Manufacturers or their agents overseas will provide repair for any unit developing a fault.
Where owner wish to undertake their own maintenance work, this should only be done by skilled
personnel in conjunction with the service manual which may be purchased directly from the
Manufacturers or their agents overseas.
Fuse
The correct fuse type is:
Note that the main function of the fuse is to make the instrument safe and limit damage in the
event of failure of one of the switching devices. If a fuse fails it is therefore very likely that the
replacement will also blow, because the supply has developed a fault; in such circumstances the
instrument will need to be returned to the manufacturer for service.
Make sure that only fuses of the required rated current and specified type are used for
replacement. The use of makeshift fuses and the short-circuiting of fuse-holders is prohibited.
To replace a fuse, first disconnect the instrument from the AC supply. Remove the 6 cover
securing screws and lift off the cover. Replace the fuse with one of the correct type and refit the
cover.
Cleaning
If the PSU requires cleaning use a cloth that is only lightly dampened with water or a mild
detergent. Polish the display window with a soft dry cloth.
WARNING! TO AVOID ELECTRIC SHOCK, OR DAMAGE TO THE PSU, NEVER ALLOW
WATER TO GET INSIDE THE CASE. TO AVOID DAMAGE TO THE CASE OR DISPLAY
WINDOW NEVER CLEAN WITH SOLVENTS.
10 Amp 250V HBC time-lag(T), 5 x 20mm.
) is 300VDC.

Maintenance

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