American Magnetics 135 & 136 Liquid Helium Level Instruments (CE-Marked) - Manual (Page 8)

iv Rev. 3
Table of Contents
4.2 IEEE-488 Communication Option ..........................................28
4.2.1 Command/return termination characters...................28
4.2.2 Communicating with the Model 135/136 ....................28
4.2.3 IEEE-488 Communication DIP Switch Settings ........30
4.2.4 IEEE-488 Command Set Reference ............................32
4.2.5 Serial Poll Status Byte.................................................36
4.3 Error Codes...............................................................................37
5 Virtual Instrument Operation .................................................39
5.1 RS-232 Virtual Instrument .....................................................39
5.1.1 Launching and initializing the RS-232 VI ..................40
5.1.2 Interacting with the running VI..................................42
5.2 IEEE-488 Virtual Instrument .................................................43
5.2.1 Launching and initializing the GPIB VI.....................44
5.2.2 Interacting with the running VI..................................45
5.2.3 Running multiple GPIB devices ..................................46
6 Service Guide ..........................................................................47
6.1 Troubleshooting Procedures ....................................................47
6.1.1 No level reading............................................................48
6.1.2 Erratic or erroneous level reading...............................49
6.1.3 Controller output does not energize ............................50
6.1.4 Unit not responding to communications .....................51
6.2 Custom Instrument Configurations ........................................52
6.2.1 Modifying the line voltage requirements ....................52
6.2.2 Enabling dirty sensor operational mode .....................52
6.2.3 Changing time adjustments from minutes to hours ..53
6.3 Additional Technical Support..................................................53
6.4 Return Authorization...............................................................53
Appendix..................................................................................55
A.1 4-20 ma Current Loop Option .................................................55
A.2 Sensor Connector J1 Wiring....................................................56
A.3 Auxiliary Connector J2 Pinout................................................57
A.4 RS-232 Cable DB-25 to DB-9 Translation ..............................58
A.5 RS-422 Cable Wiring................................................................58
Index.........................................................................................59