Re: [Emc-users] I need to connect my Voltmeter to actually read....

[Kirk W. <kwa...@wa...>]

On Sat, 2008-11-29 at 11:46 -0800, Olusegun A. wrote:
> I'm actually trying to read an analogue signal (High Voltage - say
> 1000VAC) being applied to my heavy motor. Do I need an ADC converter
> or what is the procedure?
> 
> Olusegun Abode 
> +234 8037045535 
> Email:seg...@ya...

EMC2 only has single bit and encoder inputs. Through the bit input you
can see if a bit is on or off, or you can count the bits, or measure
their frequency or PWM. The encoder input is just two bit inputs that
count quadrature encoder pulses. So if you want EMC2 to measure your
voltage, you need to convert it to a bit form. For my voltage input, I
used a serial ADC which converts a low DC voltage to a data bit stream.
This bit stream goes into one parallel port pin, where an EMC2 module I
created decodes the bit stream into a value that EMC can use wherever I
need it.

I suspect that you will need to do the same, except measuring AC at high
voltage will be a little more complicated. You could try to use my
setup, but you would need to convert your high voltage AC to a 0 to 10
Volt DC signal. I am not familiar with how to do that. You might be able
to use a multimeter that has a serial data port.

----------
Kirk
http://www.wallacecompany.com/machine_shop/