KEPCO BOP 5-20DL, Operator'S Manual

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3-14
BOP 5-20DL 081915
If the external programming source does not have sufficient amplitude to drive the BOP over its
full output range, the gain of Preamp “A” must be changed from the built-in value to suit the
application. To calculate the required components for the new gain requirement, the output
equation for Preamp “A” in the inverting configuration is used:
E
O (PREAMP “A”)
= –E
i
(R
f
/R
i
)
where E
O
(Preamp “A”) = ±2.5V, and the values of R
f
and R
i
depend on the available amplitude
of the programming source. If, for example, a ±1 volt source is available, the ratio R
f
/R
i
must be
2.5, and the two resistor values can be 10K and 24.9K respectively. The built-in resistor (R
i
=
10K) can be retained, and only R
f
must be replaced with a 24.9K metal film (1/2 watt) resistor.
The necessary connections are illustrated in Figure 3-12. Gain control can be exercised by mak-
ing R
f
a rheostat instead of a fixed resistor.
FIGURE 3-12. PROGRAMMING CIRCUIT FOR DRIVING OUTPUT VOLTAGE WITH
3.4.5 REMOTE CONTROL OF CURRENT LIMITING
For remote control of current limiting, the ± I
O
Limit Amplifiers (EXT) are disconnected from the
15V Bias source by removing jumpers between (1) - (34) and (34) - (8) at the Rear Program-
ming Connector (see Figure 3-13). An external 0 to +10V control signal is applied to terminals 8
and 34, with reference to common. This control signal programs both the negative and positive
current limit simultaneously and symmetrically over the BOP output current range.
If individual control of the ± current limits is desired, the jumper between (8) and (34) at the Rear
Programming Connector must be removed and separate control sources must be connected: 0
to +10 volts to pin 8 for the + I
O
limit, and 0 to +10 volts to pin 34 for the – I
O
limit, both with ref-
erence to common (see Figure 3-14).
NOTE: The front panel ± I
O
LIMIT controls serve as a back-up when external current limit pro-
gramming is used. These controls should be set to a value slightly larger than the
external current limits that are to be programmed.
3043886
BOP VOLTAGE
CONTROL CHANNEL
PART OF REAR PROGRAMMING CONNECTOR
+
22
28
C
+
VOLTAGE
CONTROL
VOLTAGE
PROGRAMMING
INPUT
10V
OFF
10V
ON
10K
10K
11
9
C
7
POWER
STAGE
NOTES:
1. Set MODE Switch to VOLTAGE.
2. Remote sensing shown (links removed). For
local sensing disconnect leads between S
terminals and load, then install links between
COM and S terminals and between OUT and
S terminals.
COMMON
5
Eo ZERO
-
17
+
Eo COMP
AMP
ZERO
PREAMP
"A"
-
+
2.49K
DRIVER
G
A
T
E
COM
S
OUT
S
BIPOLAR
PROGRAMMER
(EXTERNAL)
LOAD
SIGNAL
GROUND
REMOVE
SENSING LINK
REMOVE
SENSING LINK
OUT
COM
0 TO ±1 V
@
0.1mA
i
E
24.9K
f
R
i
R