AMETEK XPH 35-5 - Manual (Page 12)

Mode C: With the switch in this position only Output 2 is active; the voltage range is 0-150V
and the current range is 0-2A. The controls of Output 1 are inoperative and the display is
blanked. The red terminal of Output 1 is isolated but the black terminal remains connected
internally to the black terminal of Output 2.
Note that when the output switch of Output 1 is in the ‘ON’ position the Output lamp still lights
but the red terminal remains open-circuit.
Note also that the range and scaling of the voltage controls of Output 2 double when changing
from Mode B to Mode C, i.e. with the controls set for 60V in Mode B the output voltage
becomes 120V in Mode C. Care should therefore be taken to ensure that the outputs are
switched off before the mode is changed and that the output is set to the correct voltage before
it is switched on.
Protection
The output has intrinsic short-circuit protection and is protected from reverse voltages by a diode;
the continuous reverse current must not exceed 3 Amps, although transients can be much higher.
The output is protected against externally applied forward voltages of up to 85V (Modes A and B)
or 170V (Mode C).
Connection to the Load
The load should be connected to the positive (red) and negative (black) OUTPUT terminals. Both
are fully floating and either can be connected to ground.
Warning! Voltages above 70Vdc are hazardous live according to EN 61010-1 and great care must
be taken when using the power supply at voltages above this level.
It is highly recommended that connections are only made using leads fitted with fixed-
shroud 4mm safety plugs. Make sure that the circuit to which connections are made is
appropriately insulated; no accessible parts of the external circuit should become
hazardous live in normal or single fault condition as defined by EN61010-1.
Always make connections to the instrument with the OUTPUT off.
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.
Warning! Voltages above 70Vdc are hazardous live according to EN 61010-1 and great care must
be taken when using the power supply at voltages above this level
The maximum permissible voltage between any terminal and earth ground ( ) is 300VDC; the
maximum permissible voltage between either terminal of one output and any terminal of another
output on the same supply is also 300VDC.
All connections to the terminals must be made with the output 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.
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