California Instruments 2001RP, User And Programming Manual

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User and Programming Manual - Rev N
4.5 Function Strobe [Option]
The Function Strobe (FS) is a TTL logic level signal provided at the rear panel of the
2001RP. This signal is synchronized to any voltage and frequency output changes of the
AC source and may be used to trigger external test equipment such as oscilloscopes.
Default mode of operation
The function strobe is an active low TTL output signal. Each sync pulse lasts approximately
400
µ
sec . The output changes on the falling edge of the function strobe output.
Alternative mode of operation
The function strobe output logic uses the GPIB interface DC supply to provide the required
logic levels. If the GPIB interface is connected to the user’s PC, excessive ground noise may
prevent the function strobe from operating correctly. If this is the case, the output mode of
the function strobe may be changed to provide an open collector output instead. In this case,
the end user has to provide an external DC power supply and pull-up. A 9 Volt DC battery
may be used for this purpose. Contact California Instruments’ service department for details
on changing the operation of the FS output.
4.6 Remote Inhibit [Option]
A Remote Inhibit BNC input is located on the rear panel of the 2001RP if the -OP1 option
was specified at the time of purchase. This input may be used to kill the AC source output
using an external control signal.
Default mode of operation
If the Remote Inhibit input is left unconnected, the output of the AC source can be turned on
using the ON/OFF button on the front panel or the appropriate bus command. To disable the
output relay, a logic low level or a contact closure needs to be present across the terminals
of the BNC (RI) connector.
Typical use of the RI input is in rack and stack systems where the RI input is wired to a
switch that detects removal of the rear panel. This input may also be used to simultaneously
shut down multiple AC power sources.
Note that the RI input has an internal pull up resistor to TTL logic high. When the RI input
cable is disconnected, the output will recover and the output relay will be closed
automatically.
36 April 2007 2001RP