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Jamie
 
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Default Use of Square Wave Generator on DMM

Ralph Mowery wrote:

"Jamie" t wrote in message
...

wrote:


My meter has a 2V peak 30 to 40 Hz square wave generator and I am
wondering how I can use it in troubleshooting. What can I test
in-circuit? How? Anything to watch out for, things I should not do?


maybe that is part of a 4..20 ma output option
to calibrate devices?



HOw did you come up with the 4-20 ma loop option ? Most 20 ma loops are
setup to use about a 24 volt supply. Some of them will have a 250 ohm
resistor in them to convert the 4-20 ma to a 1 to 5 volt signal for the
readout device. This takes atleast 5 volts. The loops usually work on DC.
I have used some test equipment that will ramp up in steps of 25% but it is
much slower than 30 hz. Maybe every .5 to 1 second. I have used some VOMs
that have a miliamp driver built in. Fluke makes one.

I am sure there are applications that require that 2 volt square wave
signal, but I have not seen any. What else does the meter do ?



because my meter has a pulse generator as a signal along with a 4..20
output to be used in calibrating current controlled devices.
its used to supply a signal into the control device or to actually
pulse the "ma" output line to pulse the actuator it self.
its programmable.
also, my meter uses a 9 volt source but has a DC-DC converter to
generate 24 volts for the current source with scale able current out and
monitoring.

i don't know the meter that is in use, only going by my experience and
suggesting what it could be.

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