KEPCO BOP 5-20DL, Operator'S Manual

Page: 42 / 70

3-8
BOP 5-20DL 081915
3.3.4 LOCAL CONTROL OF VOLTAGE LIMITING
Figure 3-5 shows the Voltage Limiting circuit configured for local sensing and local (front panel)
control. The circuit functions in a manner similar to the I
O
Limit circuit described previously (refer
to PAR. 3.3.2), except that the voltage limit feedback is derived by means of a voltage divider
across the BOP output.
In the local (front panel) control mode, as well as in the external control mode, a 0 to 10 volt sig-
nal, applied at the inverting inputs of the ± E
O
Limit Comparison amplifiers, will control the volt-
age limit point over the entire output current range of each BOP model. For the internal (front
panel) control mode, the control signal is derived across both 10 volt reference sources, applied
by means of the ± E
O
Limit controls to the internal ± E
O
Limit amplifiers and directed to the
respective inputs of the ± E
O
Limit Comparison amplifiers. In the internal control mode, both ±E
O
Limit Amplifiers (EXT) are biased off by the 15V bias source.
FIGURE 3-5. BOP (±) VOLTAGE LIMITING CIRCUIT (LOCAL CONTROL, LOCAL SENSING)
3043877
+
22
28
C
+
10V
10V
POWER
STAGE
-
+
G
A
T
E
COM
S
OUT
S
-
+
+
-
6
32
3
+
+
-
+
-
+
-
(+)Eo LIMIT-
AMP (EXT)
(+)Eo LIMIT-
AMP (INT)
(-)Eo LIMIT-
AMP (INT)
(-)Eo LIMIT-
AMP (EXT)
(+)Eo LIMIT
CONTROL
BIAS 15V
(-)Eo LIMIT
CONTROL
(+)Eo LIMIT-
COMP AMP
(-)Eo LIMIT-
COMP AMP
DRIVER
COMMON
BOP Eo
LIMIT CHANNEL
PART OF REAR PROGRAMMING CONNECTOR
57.6K
57.6K
NOTES:
1. Local Sensing shown (links installed between COM
and S and between OUT and S terminals).
2. On Rear Programming Connector install jumpers between
terminals (3) and (32) and between (32) and (6).
LOAD
SIGNAL
GROUND