225 Series User’s Manual
8
118120-001-Rev. A
3.4.4
SHUTTING THE HIGH VOLTAGE
OUTPUT OFF (“Z”)
The user may turn off the high voltage output without
affecting the currently active programmed value. The
syntax is:
“Z” the single ASCII character
This has the same effect as executing the device clear
bus command.
3.4.5
RESTORING THE HIGH VOLTAGE
OUTPUT (“R”)
The high voltage output may be turned back on to the
currently active programming value after having been
shut off by a user command “Z” or by a trip due to
overload. The sytax is:
“R” the single ASCII character
The high voltage output will return to the value that was
programmed before the shut down. If the output was
turned off by an overload trip, the cause of the overload
should be corrected before trying to restore the output
voltage or the trip will occur again.
3.4.6
SELECTING THE OVERLOAD TRIP
RESPONSE (“OE” & “OC”)
When the unit detects that the output has exceeded one
of the user programmed limits, it may respond by
shutting off the high voltage output, also called tripping.
The user may select that the power supply trip itself for a
voltage overload only, for a current overload only, for a
voltage or a current overload, or for neither. The syntax
is:
“OE
{numeric}”
“OC
{numeric}”
Where {numeric} is the ASCII character for 0, 1, or 2
and:
OE2 Establishes that the unit cannot be
programming to a voltage value above the voltage limit
setting.
OE1
Enables the unit to shut down its output upon
detection of an output voltage above the voltage limit
setting.
OE0
Establishes that the unit will not shut down its
output in response to the detection of an output voltage
above the voltage limit setting.
OC1
Enables the unit to shut down its output upon
detection of an output current above the current limit
setting.
OC1
Establishes that the unit will not shut down its
output in response to the detection of an overload current
greater than the current limit setting.
3.4.7 SELECTING THE OVERLOAD SERVICE
REQUEST RESPONSE (“SE & “SC”)
Just as the unit can be made to shut off the output in
response to an overload, it can also be made to generate a
service request to the GPIB controller in response to an
overload. The syntax is:
“SE {numeric}”
“SC
{numeric}”
where {numeric} is the ASCII byte for 0 or 1 and:
SE1
Enables SRQ in response to an overvoltage
detection
SE0
Disables SRQ in response to an overvoltage
detection
SC1
Enables SRQ in response to an overcurrent
detection
SC0
Disables SRQ in response to an overcurrent
detection
When the unit sends an SRQ to the GPIB controller, the
user should execute a serial poll of the unit to obtain its
status byte. Please note that the overload response
choices and the service request choices operate
independently of each other.
3.4.8 TRIGGERING METER READINGS OF
THE OUTPUT (“T”)
Each unit has the capability to perform meter readings of
its output voltage and current. The user may trigger a
reading of the output voltage, the output current or both.
The syntax is:
“T
{numeric}”
Where {numeric} is the single ASCII character for 0, 1 or
2 and:
T0 Triggers
a
measurement
of the output voltage
and current
T1
Triggers a measurement of the output current
only
After receiving one of the “T” commands, the unit will
return a character string containing output status (Normal,
Tripped or Shutdown) and voltage and/or current
readings. The numerical formats are those used to enter
voltage and current values.
