Ametek Elgar ReFlex Power Operation Manual page 301

Active Loads
M
7.5.2
ODES OF
C
ONSTANT
In this mode, the Active Load maintains the input current precisely regulated to
the current setting while the source voltage varies with user requirements.
C
ONSTANT
In this mode, the Active Load maintains the input resistance setpoint by
adjusting the current as a function of the applied voltage.
L C
7.5.3
OAD ONNECTION
The input of the Active Load module is isolated from chassis ground, allowing
positive, negative, or floating inputs 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 load is required to meet accuracy and regulation
specifications. The sense leads should be connected to the point in the source
circuit where the voltage is to be precisely measured. If a distribution bus is
utilized, the point of voltage sensing is important to ensure that the voltage
measurement is acceptable. In general, the point of sensing is selected to
minimize interaction through line drops caused by source currents.
CAUTION
Operating the active load with either the positive or negative input lead
at greater than the float voltage specification limit above chassis ground
could result in damage to the module.
S
TANDALONE
A single source is connected directly to the front panel input terminals, and the
Active Load module is configured to operate in the standalone mode. Twist the
source wires or maintain them closely in parallel for their entire length to
minimize parasitic inductance and coupling from external circuits. Use the
heaviest gauge practical to minimize line drop. The remote sense wires should
be twisted, and may need shielding depending on the electrical noise
environment of the application. Figure 7-9 shows a standalone load connection
with remote sensing.
7-26
O
PERATION
C
URRENT
R
ESISTANCE
C
ONFIGURATION
C
ONFIGURATION
ReFlex Power™
M380056-01 Rev L