KEPCO BHK-MG Series, Operator'S Manual

Page: 105 / 150

BHK-1/2-MG 030916
3-59
The output current of the series combination operating in current mode is determined by the out-
put current of the master:
Io = Io
M
, where Io
M
is the output current of the master, in mA.
The load voltage is Eo = Io
M
x R
LOAD
where Eo is the output voltage of the series combination.
The split of voltage between the master and slave is the same as for voltage mode (see eq1
above); when R
EXT
(in K-ohms) = E
O
max
S
(in Volts), the slave and master output voltage are
the same: Eo
S
= Eo
M
= Eo / 2.
RECOMMENDED PROCEDURE. The following steps are recommended to ensure the combi-
nation of power supplies (power assembly) configured for master-slave series (tracking) opera-
tion is connected and set up properly for current mode operation.
1. With the units turned off, perform all external wiring (see Figure 3-22). Use R
EXT
= E
O
max
M
(see PAR. 3.9.2.2.1) If possible, use a properly rated switch between the power supply and
the load.
2. Apply power to the units:
a. If a load switch is used, close the switch. Set POWER switch of both units to up position
to turn power on.
b. If load switch is not used, Set POWER switch of both units to up position to turn power
on, then press OUTPUT ON/OFF key once on each unit to disable the output.
3. Program slave unit as follows:
a. Program Iset
S
to approximately 1.01 to 1.02 x nominal output current Io for power
assembly. This maximum current limit is never used except in the unlikely event that
the current limit of master unit is not working.
b. Program Vset
S
to 0.
c. Program overcurrent value of slave unit (Iocset
S
) to 1.1 x Iset
S
(step 3a).
d. Program overvoltage value of slave unit (Vovset
S
) to
where:
• E
LIM
is the voltage limit of the power assembly.
• E
O
max
M
is the nominal maximum voltage of the master unit (e.g. for BHK 1000-0.2MG
= 1000 volts).
• E
O
max
S
is the nominal maximum voltage of the slave unit.
4. Program master unit as follows:
a. Program Iset
M
to the desired output current, I
O
of the power assembly.
b. Program Vset
M
to .
c. Program overcurrent value of master unit (Iocset
M
) to 1.1 x Iset
M
(step 4a).
1.1
 
E
L I M
 
E o m a x
S
 
E o m a x
M
E o m a x
S
+
-------------------------------------------------------------------
E
L I M
 
E o m a x M
 
E o m a x M E o m a x S
+
 
----------------------------------------------------------------