Fluke 5502A, Operator'S Manual

Page: 145 / 378

5-3
Introduction
This chapter gives methods to operate the Calibrator by remote control.

Warning
The 5502A Calibrator can output voltages to a maximum of
1020 V rms and must be programmed with caution to prevent
hazardous voltage production without sufficient warning to the
operator.
Write programs carefully and test them extensively to make
sure of safe operation of the Calibrator. Fluke Calibration
recommends that you include error-catching routines in your
programs. These error-catching routines will help you find
programming errors that can cause the Calibrator to act other
than intended. You can program the Calibrator to cause an SRQ
when an error is found by setting the Service Request Enable
(SRQ) register. The subsequent skeleton program has error-
catching code:
10 PRINT @4,
“
*CLS
”
! Clear status
20 PRINT @4,
“
*SRE 8
”
! Set SRE Error Available
30 ON SRQ GOTO 1000 ! Enable SRQ Function
100 ! Place body of program here
900
STOP ! End of program
1000 REM Start of SRQ Handler
! Start routine
1010 PRINT @4,
“
FAULT?
”
! Request fault code
1020 INPUT @4, A% ! Input fault code
1030 PRINT @4,
“
EXPLAIN?
“;
A% ! Request fault text
1040 INPUT @4, A$ ! Input fault text
1050 PRINT
“
Fault
“;
A$
”
detected
”
! Print message
1060 PRINT @4,
“
STBY
”
! Place 5502A in standby
1070 STOP
Remote control can be interactive and you can control each step from a terminal, or with
the control of a computer sequence that operates the Calibrator in an automated system.
The Calibrator rear panel has three ports for remote operations: IEEE-488 parallel port
(also known as a General Purpose Interface Bus, or GPIB port), and two RS-232 serial
ports, SERIAL 1 FROM HOST and SERIAL 2 TO UUT.
IEEE-488 The IEEE-488 parallel port is usually used in larger control and calibration
systems. An IEEE-488 system is more costly to set up, but can control multiple
Calibrators and multiple UUTs. Also, parallel system throughput is faster than serial
system throughput. The controller in an IEEE-488 system is typically a MS-DOS
compatible personal computer (PC) that has one or more IEEE-488 ports. You can write
your own computer sequences for system operation with the command set, or you can
purchase optional Fluke Calibration software MET/CAL Plus. Typical IEEE-488
configurations are shown in Figure 5-1. The configuration that shows the PC with two
IEEE-488 ports is used with MET/CAL. For this configuration, put the Units Under Test
(UUTs) on isolated IEEE-488 port. You can also “piggy-back” the connectors on one
IEEE-488 port.