AMETEK ReFlex - Manual (Page 117)

AC Power Supplies ReFlex Power™
4-32 M380056-01 Rev K
C ONSTANT V OLTAGE
The AC power supply will operate in constant–voltage regulation whenever the
load current is less than the programmed current setting. In this mode, the
power supply maintains the output voltage precisely regulated to the
programmed voltage setting while the load current varies with the load
requirements. This condition is maintained as long as the load current is less
than the current setting. If the load resistance decreases to where the load
current attempts to exceed the current setting, the output current is then
regulated at the programmed current setting, and the output voltage decreases
until that condition is satisfied. This is the automatic crossover point to
constant–current mode of operation.
C ONSTANT C URRENT
The AC power supply will operate in constant–current mode whenever the load
resistance times the programmed current setting is less than the programmed
voltage setting. In this mode, the power supply maintains the output current
precisely regulated to the current setting while the load voltage varies with load
requirements. This condition is maintained as long as the load resistance is
less than the voltage setting divided by the current setting. If the load
resistance increases to where the load voltage attempts to exceed the voltage
setting, the output voltage is then regulated to the programmed voltage setting,
and the output current decreases until that condition is satisfied. This is the
automatic crossover point to constant–voltage mode of operation.
4.5.3 L
OAD
C
ONNECTION
C
ONFIGURATIONS
The output of the AC power supply module is isolated from chassis ground,
allowing either positive, negative, or floating outputs with respect to chassis
ground. Connections to the load are made at the front panel output connector
terminals. Ensure that a wire gauge is utilized that can carry the programmed
current without overheating.
Remote sensing of the output voltage is required to meet accuracy and
regulation specifications. The sense leads should be connected to the point in
the load circuit where the voltage is to be precisely regulated. If a distribution bus
is utilized for multiple loads, the point of voltage sensing is important to ensure
that the voltage regulation is acceptable for all of the loads. In general, the point
of sensing is selected to minimize interaction of the various loads through line
drops caused by their load currents.
CAUTION
Operating the power supply with either output lead at greater than the float
voltage specification limit above chassis ground could result in damage to
the module.