KEPCO MBT Series - Manual (Page 58)

3-20
MBTSVC111609
If the power supply is operating in a remote configuration, setting output current or current limit
can also be influenced by the last command issued to the power supply before the unit is put
into Local Mode. If the power supply was commanded to operate in Current mode before being
set into Local mode, Table 3-9 indicates that if the load allows the power supply to operate in
current mode, Iadj and the keypad entries adjust either programmed or actual output current
depending on whether the load is disabled or enabled. If the load forces the power supply to
operate in voltage mode, Iadj and keypad entries will adjust actual current limit, contrary to the
display indication.
Refer to PAR. 3.2.1.7.3 for procedure.
3.2.1.7.2 USING IADJ AND NUMERIC KEYS — MR, MGR MODELS
The Iadj and numeric keys can be used to adjust either output current or current limit (either the
actual value or the programmed value). The effect of the numeric keypad entries is dependent
upon the model, commanded mode, whether the output is enabled or disabled, and the load.
For MR and MGR models, when the output is disabled, the load is disconnected from the power
supply if the power supply is operating in Voltage mode, or the power supply output is short
circuited if the unit is operating in Current mode.
If the output is enabled, the power supply can operate either in voltage mode or current mode,
as determined by both the programmed output values (Voltage or Current) and the value of the
load. If the power supply is commanded to be in Voltage mode, the power supply will actually
operate in voltage mode when R
L
≥ V
Prog
/ I
Prog
, and current mode (forced) when R
L
< V
Prog
/
I
Prog
. Similarly if the power supply is commanded to be in Current mode, the power supply will
actually operate in Current mode when R
L
< V
Prog
/ I
Prog
, and in Voltage mode (forced) when
R
L
≥ V
Prog
/
Prog
.
TABLE 3-9. USING IADJ AND KEYPAD ENTRIES TO SET OUTPUT
CURRENT/CURRENT LIMIT — MODELS M, MG
POWER SUPPLY STATUS BEFORE Iadj PRESSED EFFECT AFTER Iadj PRESSED
COMMANDED
MODE
OUTPUT
ENABLED/
DISABLED
ACTUAL MODE ***
(DICTATED BY
LOAD)
DISPLAY
INDICATION
NUMERIC VALUE
SET BY KEYPAD
ADJUSTS:
CURRENT * DISABLED CURRENT CONST CURR = Programmed output current
CURRENT * ENABLED CURRENT CONST CURR = Actual output current
CURRENT * ENABLED VOLTAGE **** CONST CURR = Actual current limit **
VOLTAGE DISABLED VOLTAGE CURR LIMIT = Programmed current limit
VOLTAGE ENABLED VOLTAGE CURR LIMIT = Actual current limit
VOLTAGE ENABLED CURRENT **** CURR LIMIT = Actual output current **
* If the unit was programmed to Current mode remotely before being set to Local Mode, the unit will stay in current
mode until a Voltage Mode command is received.
** “Overload” error message placed in error buffer (for use when operating in Remote mode).
*** Actual mode is indicated by the VOLTAGE MODE and CURRENT MODE status LED’s.
**** Condition where load forces power supply mode.