3-2
JQE SPECIAL SVC 092611
3.2.2
REMOTE ERROR SENSING (SEE FIGURE 3-1B.)
Remove the links between terminals (1) and (2) and between terminals (3) and (4) of TB501 at
the rear panel. Specified regulation performance DIRECTLY AT THE LOAD requires the use of
remote error sensing. A twisted, pair of wires from the sensing terminals directly to the load will
compensate for load wire voltage drops up to 1.0 volt per wire (Refer to Figure 3-1B). Observe
polarities: for example, the positive sensing wire (from TB 501 terminal 2) goes to the positive
load terminal (connected to + OUTPUT terminal).
To keep the DC voltage drop in the load connecting wires to a minimum, and to preserve the
dynamic characteristics of the power supply (AC stability, output impedance and recovery time),
load wires should be as short as possible and as large in diameter as practicable, rated at least
for nominal output current. Error sensing leads should be #22 AWG and as short as possible.
Both lead pairs should preferably be tightly twisted. For minimum ripple and noise pick-up, the
error sensing leads may be shielded. The shield should be returned to the ground point of the
JQE Special.
3.2.3
GROUNDED LOAD CONNECTION
If the load has one end connected to EARTH-GND, then connect the load termination con-
nected to EARTH-GND to +OUTPUT at the rear panel for better output noise performance (see
Figure 3-2A). For this configuration the voltage across the load will be negative with respect to
chassis GND.
If the load is floating, but it is desired to have the JQE having the output with a certain polarity
with respect to chassis GND, connect locally, either –OUTPUT terminal to chassis GND for a
positive output voltage referenced to chassis GND (see Figure 3-2B), or cOUTPUT ter-
minal to GND for a negative output voltage referenced to chassis GND (see Figure 3-2C).
FIGURE 3-2. GROUNDED LOAD CONNECTIONS
+OUTPUT
-OUTPUT
TWISTED
PAIR
GROUNDED LOAD CONNECTION,
FOR A NEGATIVE OUTPUT
WITHOUT REMOTE ERROR SENSING
TWISTED
PAIR
-OUTPUT
+OUTPUT
NEGATIVE OUTPUT
REFERENCED TO CHASSIS
WITHOUT REMOTE ERROR SENSING
POSITIVE OUTPUT
REFERENCED TO CHASSIS
WITHOUT REMOTE ERROR SENSING
+OUTPUT
-OUTPUT
TWISTED
PAIR
