Micrologix 1100, 1763L16BBB, Processor Output Problem

I'm building a model traffic light with my Micrologix 1100 processor (1763L16BBB) and two of the lamps that are controlled by relay outputs are coming on and off as intended but the lamps that are being controlled by FET outputs are not coming on. Meanwhile, they are turning on and off appropriately on the LCD screen on the processor. I think the bulbs are not creating enough "load" to make the FET turn on and so I want to put some resistors across them. I'm yet to try anyway. What else may be the problem that is keeping the bulbs being controlled by FET outputs from coming on and off that I need to check or have to do in addition to adding the resistors? Thanks for any suggestions anyone is able to give.

Check the manual and make sure you have the FET outputs wired correctly.

Unlike relay outputs which just need voltage on the Common termincal of the relay output (VACDC0, 1, 2, etc.) the Transistor outputs require both the positive and common of your power supply wired to them properly to work.

http://literature.rockwellautomation.com/idc/groups/literature/documents/in/1763-in001_-en-p.pdf
Page 16 of that document.

Tharon said:

Check the manual and make sure you have the FET outputs wired correctly.

Unlike relay outputs which just need voltage on the Common termincal of the relay output (VACDC0, 1, 2, etc.) the Transistor outputs require both the positive and common of your power supply wired to them properly to work.

http://literature.rockwellautomation.com/idc/groups/literature/documents/in/1763-in001_-en-p.pdf
Page 16 of that document.

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Yes, they are wired properly. I've verified and am getting 24v. Thanks.

Yes, they are wired properly. I've verified and am getting 24v. Thanks.

Click to expand...

With solid state devices you are going to see voltage whether its on or off.

Is the load polarity sensitive. Double check.

Mickey said:

With solid state devices you are going to see voltage whether its on or off.

Is the load polarity sensitive. Double check.

Click to expand...

I meant to say I verified the voltage at the terminals to the FET outputs and got 24v.

Yes, the load polarity is sensitive. The -ve side goes throught the load (lamp) which is the same for the relay outputs. I wired it just like the lamps for the relay outputs which are switching as intended. Thanks.

Can you post a picture of your wiring schematic for our reference?

Tharon said:

Can you post a picture of your wiring schematic for our reference?

Click to expand...

I've got it folks. I failed to make a simple loop. Taking the -ve side of the power supply to the COMM of the lamps. I appreciate all inputs. Thanks.