Need Help/Advice about DC Output Module

Hello everyone. this is my first time posting on this forums so please forgive me if the format of my question is unclear.

background information: i am working on a project which is to automate a greenhouse using PLC 5/40L.

The first task is to program the DC Output Module to produce a constant 24V DC. The output of this module will be use to power our LED grow lights, the end goal is to have a timer for which it will power the lights for 8 hrs and turn off, and repeat the next day.

The DC module has been inserted and configured according to its data sheet. Now, i have no experience in PLC and have no idea how to begin, so i need advice on how approach programming this to accomplish our task. The software we have is RSLogix 5.

I will attach pictures of the setup so far.

Related Info:
Cat. no. 1771-OBD Output Module
Chassis Type: 1771-A2B (8Slots) - PLC - 5/40L

Thank you so much for taking the time to read this post.
Have an awesome day

First off I hope you understand that that module is only callable of 2 amps (or 48 watts) per output with a total module output of 8 amps (or 192 watts). Any larger load than that you going to need some kind of contactor/power relay on the output.

If your using 2 slot addressing then the output address will be O:002/00 thru O:002/17, remember PLC-5 IO is always octal addressing.
If your using 1 slot addressing then the output address will be O:004/00 thru O:004/17.

Power the lights from your 24VDC supply, through a relay that is controlled from your output card. Not directly from the output card.

rupej said:

Power the lights from your 24VDC supply, through a relay that is controlled from your output card. Not directly from the output card.

Click to expand...

Thank you for the reply,

How would i begin to program this in RSLogix 5?

I have an 1771 - OW 16/B Relay Contact Output Module

I will attach a picture of the wiring diagram for this module.

Ok- you said DC output module which is different. Relay outputs are better but I would still use separate relays to keep from wearing out your expensive card.

You need to look into using timers. TON, RTO. There are multiple ways to do this. Check the manual or help file in RSLogix 5 for examples of how to use timers.

rupej said:

Power the lights from your 24VDC supply, through a relay that is controlled from your output card. Not directly from the output card.

Click to expand...

rupej said:

Ok- you said DC output module which is different. Relay outputs are better but I would still use separate relays to keep from wearing out your expensive card.

You need to look into using timers. TON, RTO. There are multiple ways to do this. Check the manual or help file in RSLogix 5 for examples of how to use timers.

Click to expand...

Sorry for the confusion. I will do what you suggested, thanks.

These PLC 5s must be unkillable if people are still doing projects with them!

Why not?

Geoff White said:

These PLC 5s must be unkillable if people are still doing projects with them!

Click to expand...

It's a greenhouse, I have a PLC5/20C, four slot chassis, two SIM cards and internal power all for under $500 invested that I use in a trainer. Reliable and easy to find parts, are still widely used. That's why I still support one in my trainer, people are asking for hands-on training even with 5 series processors.

Regards,
Sydney