AnsweredAssumed Answered

3458A ACV overload

Question asked by brian@boeing on Nov 14, 2011
I'm setting up and taking various measurements remotely. One thing that has me puzzled is the AC V measurements. I had set up for an input of over 1.2VAC on the 1VAC range, using a function generator set for 60Hz sine, amplitude 1.5 VRMS. Iexpected an overload indication. Instead, it returned the value. I had to raise the voltage up to over 3.5 V to get an overload. We have to indicate overload in this situation.

I didn't have any problem with DCV. Anything at 120% of range would return overload.


I had looked at the manual, and it had this table:

For ACV or ACDCV:                 
-------------------------------
max._input     Selects   Full
Parameter      Range     Scale
-------------------------------
–1 or AUTO     Autorange            
0 to .12       10mV      12mV       
>.012 to .12   100mV     120mV       
>.12 to 1.2    1V        1.2V       
>1.2 to 12     10V       12V       
>12 to 120     100V      120V       
>120 to 1E3    1000V     1050V     


Here is the NISpy traffic for my setup and measurement:

viOpenDefaultRM (0x003666D8)
viOpen (0x003666D8, "GPIB0::22::INSTR", 0, 5000, 0x0051EC78)
viSetAttribute (GPIB0::22::INSTR (0x0051EC78), TERMCHAR_EN, VI_TRUE)
viOpen (0x003666D8, "GPIB0::INTFC", 0, 5000, 0x0051FB60)
viClear (GPIB0::22::INSTR (0x0051EC78))
viWrite (GPIB0::22::INSTR (0x0051EC78), "PRESET NORM;TARM HOLD...", 26, NULL)
viWrite (GPIB0::22::INSTR (0x0051EC78), "*CLS.", 5, NULL)
viClear (GPIB0::22::INSTR (0x0051EC78))
viWrite (GPIB0::22::INSTR (0x0051EC78), "PRESET NORM;TARM HOLD...", 26, NULL)
viGpibControlREN (GPIB0::22::INSTR (0x0051EC78), 4)
viWrite (GPIB0::22::INSTR (0x0051EC78), "TRIG AUTO.", 10, NULL)
viWrite (GPIB0::22::INSTR (0x0051EC78), "MEM OFF.", 8, NULL)
viWrite (GPIB0::22::INSTR (0x0051EC78), "RQS 128;TARM SGL.", 17, NULL)
viGpibControlREN (GPIB0::22::INSTR (0x0051EC78), 4)
viWrite (GPIB0::22::INSTR (0x0051EC78), "TRIG AUTO.", 10, NULL)
viWrite (GPIB0::22::INSTR (0x0051EC78), "MEM OFF.", 8, NULL)
viWrite (GPIB0::22::INSTR (0x0051EC78), "RQS 128;TARM SGL.", 17, NULL)
viWrite (GPIB0::22::INSTR (0x0051EC78), "FUNC ACV,.1E1.", 14, NULL)
viGpibControlREN (GPIB0::22::INSTR (0x0051EC78), 4)
viWrite (GPIB0::22::INSTR (0x0051EC78), "TRIG AUTO.", 10, NULL)
viWrite (GPIB0::22::INSTR (0x0051EC78), "MEM OFF.", 8, NULL)
viWrite (GPIB0::22::INSTR (0x0051EC78), "RQS 128;TARM SGL.", 17, NULL)
viGetAttribute (GPIB0::INTFC (0x0051FB60), GPIB_SRQ_
viRead (GPIB0::22::INSTR (0x0051EC78), " 1.495829501E+00..", 1024, 18)
viClose (GPIB0::INTFC (0x0051FB60))
viClose (GPIB0::22::INSTR (0x0051EC78))
viClose (0x003666D8)  

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