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GMC-I Messtechnik GmbH
4
Status Register Reporting
SCPI Status Register
The electronic load has four status register to record its status.
They are the Status Byte register, the Standard Event register, the
Questionable Status register, and the Operation Status register.
The Status Byte register summarizes all of the status events from
all status registers. The list below is the description for all status
registers.
BIT
Signal
Meaning
Operation Status register
0
CAL
A calibration calculation is in progress.
1
WTG
Waiting for trigger.
Questionable Status register
0
VF
Voltage Error
It is caused by the reversed voltage or the over-voltage;
VF remains set till the “
INP:PROT:CLE
” is received.
1
OV
Over-voltage
When the Over-voltage occurs, the load is turned off, and
OV/OF is set at the same time. OV/OF remain set till the
over-voltage condition is removed and the
“
INP:PROT:CLE
” is received.
2
OC
Over-current
When the current exceeds the protection current limit, OC
is set, and remains set till the over-current condition is re-
moved. However, if OC remain set for the specified delay
period, PS will be set, and the load is turned off. In this
case, PS/OC remain set till the over-current condition is
removed, and the “
INP:PROT:CLE
” is received.
3
OP
Over-power
When over-power occurs, the load is turned off, and OP/
PS are set. OP/PS remain set till the over-power condition
is removed, and the “
INP:PROT:CLE
” is received.
4
RV
Reverse Voltage on input
When reverse voltage occurs, RV/VF are set. RV is reset
after the reverse voltage is removed, but VF remains set
till the “INP:PROT:CLE” is received.
5
OT
Over-temperature
When over-power occurs, the load is turned off, and OP/
PS are set. OP/PS remain set till the temperature is re-
duced by the fan and the “INP:PROT:CLE” is received.
6
CC
Constant Current mode
7
CV
Constant Voltage mode
8
CP
Constant Power mode
9
CR
Constant Resistance mode
13
PS
Protection Shutdown
The electronic load is turned off due to over-current, over-
power or over-temperature; the PS is set and remain set
till the “INP:PROT:CLE” is received.
Standard Event register
0
OPC
Operation Complete
The load has completed all pending operations. Program-
ming *OPC causes this bit to be set when the load com-
pletes al pending operations.
2
QYE
Query Error
The output queue was read when no data was present.
Errors in the range of -499 to -400 can set QYE.
3
DDE
Device Dependent Error
Memory was lost. Errors in the range of -399 to -300 can
set DDE.
4
EXE
Execution Error
A command parameter was outside the legal range or incon-
sistent with the electronic load` s operation, or the command
could not be executed due to some operating condition. Er-
rors in the range of -299 to -200 can set EXE.
5
CME
Command Error
A syntax or semantic error has occurred. Errors in the
range of -199 to -100 can set CME.
7
PON
Power On
This bit is always set when the load is turned on.
Status Byte register
3
QUES
Questionable
If an enabled questionable status register is affected, the
QUES is set.
4
MAV
Message Available
If the Output Queue contains data, the MAV is set.
5
ESB
Event Status Bit
If a Standard Event Enable register is affected, the ESB is set.
6
MSS RQS
During a serial poll, RQS (Request Service) is returned and
cleared. For an *STB? query, MSS (Master Summary Sta-
tus) is returned without being cleared.
7
OPER
Operation
If an enabled Operation Status register is affected, the
OPER is set.
