KEPCO BOP 1KW-MG Operator Manual, Firmware Ver.3.05 to 4.07 - Manual (Page 82)

3-18
BOP HIPWR 031912
capable of delivering ±28A in current mode can be configured to allow current to be adjusted
from –0.5A to +10A by setting –Current Min to –0.5 and +Voltage Max to +10. Adjustment
range is between 0 and E
Onom
for voltage and 0 and I
Onom
for current. Note that these soft-
ware limits are not the same as the Protect Limits described in PAR. 3.3.4.2.
The main channel software limit values can be lowered (closer to zero) by the user, e.g., to pre-
vent inadvertent damage to a specific circuit under test. When the maximum/minimum values
are lowered, the unit will not accept values that exceed the new software limits. If the user
attempts to enter a value that exceeds the software limit, the unit will continue to function. in
local mode the Exceeding Maximum Allowed Value message is displayed, and the output
will be clamped to the main channel software limit (maximum/minimum) value. In remote mode
the command is considered invalid and is disregarded: a 120 error is produced and the mes-
sage Voltage Out of Range or Current Out of Range is displayed on the front panel.
The main channel software limits are always in effect, even when the unit is controlled by an
external reference. If main channel software limits are changed from the default, the pro-
tection limits must be changed to correspond to the new software limits (see PAR.
3.3.4.2). As an example, changing +Voltage Max and –Voltage Min of a BOP 36-28MG to ±3V,
respectively, causes the unit to behave as if it was a BOP 3-28MG. In this case it is important to
change the +V Protect Max and –V Protect Min limits (e.g., to ±3.3V, respectively) so that the
load is protected when operating in Current Mode.
1. Press
%
from the power-up screen to enter the General Setup menu, then highlight
Max/Min Settings.
2. Press
!
to enter the Max/Min Settings submenu (Figure 3-7 and Table 3-5). (If a Password
is required, see PAR. 3.2.4.4 for instructions.)
3. Highlight the voltage or current max/min value and press
!
to change it. Software limits
are absolute values (do not use minus sign for negative limits). Use number keys to change
the setting, then
$
to save.
4. When complete, press
$
to save for power-up,
#
to abort, or
%
to apply the changes
(without saving for power-up) and exit.
5. Upon return to the power-up screen, the main channel (voltage or current) is compared
against the main channel limits in effect. If the main channel exceeds the limit, it is set to
zero.
3.3.4.2 CHANGING MAXIMUM/MINIMUM PROTECTION SOFTWARE-CONTROLLED LIMITS
The ± protection limits are software limits that establish the maximum and minimum (maximum
negative) allowable levels of output voltage in current mode and current in voltage mode. The
default protection limits are 1% above E
Omax
or 1% above I
Omax
.
The protect channel limits are +V (voltage) Protect max, –V Protect min, +C (current) Protect
Max and –C Protect min (see Table 3-4); these prevent the unit from delivering voltage or cur-
rent that exceed these settings. In voltage mode the current protect channel is clamped to the
limit value; in current mode the voltage protect channel is clamped to the limit value. Adjustment
range is between a minimum (box) value (see Figure 1-3) and 1% above the nominal (rated)
value.