Author Topic: Analogue input connector  (Read 10436 times)

Petty_boy

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Analogue input connector
« on: July 15, 2009, 02:28:45 PM »
Hi,

I'm using a 0-5V sensor on one of the AI on my TMD2424, sometimes, usually after power up the ADC reads zero, I give the 5V connector and the analogue input connector a tap and bingo, I have a reading.

Is the 0VDC for the analogue supply and the PLC 0VDC power supply connected internally?

I have removed and reconnected the connector a couple of time but there was no obvious sign of corrosion or mis-alignment.

I'll try another channel.

Marcus

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Re:Analogue input connector
« Reply #1 on: July 15, 2009, 04:11:20 PM »
The analog and digital ground are internally linked.

If the analog input is not connected then what you normally should see is the reading going to near the level indicated by its neighboring pin. If all the analog inputs are not connected it tends to float to the highest value which is 4092.
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Petty_boy

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Re:Analogue input connector
« Reply #2 on: July 16, 2009, 01:18:30 AM »
Hi,

I don't see any floating voltage on any of the inputs, just every now and then the ADC reading on the LCD is 0, I give the connector a tap and all is good again??

I'll have a look again and try to see what's happening,  I'll swap the connector with a spare and see if it helps.

Cheers.