Two coils energized at end of rung

Is energizing two coils in parralel at end of rung a good programming practice?

It is perfectly acceptable.

Just like hardwired logic allows two relays to be connected in parrallel, PLC logic has no problem with this.

You COULD arguie that it can cause some confusion, as you would have two adresses in the program with the same meaning (ie. function).
But I can think of some situations where it could be meaningful:
F.ex. when an actuator is activated by one output, and a warning lamp is activated by another output (and you want to seperate the outputs from each other - sometimes it is easier to just have two outputs rather than going via a relay).
OR F.ex. you have two program functions that have two different control bits, and you want to fire them both at the same time.

Yep, nothing wrong with it.
I think you are permitted to extend branch about seventy some times with A-B PLC-5 & SLC-500. In the A.I. series you are only limited by the PLC memory. You can only nest for four branches.

Roger

I use multiple outputs in a rung all the time. For example, an alarm routine may contain a latch, acknowledge bit, Diff up to re-trigger a strobe, output for a SCADA system (grouped to improve read times), a flashing output for a light and then used in conjunction with a series of bit count instructions to control other functions etc.
I get really annoyed when a PLC will only allow multiple outputs that do no have separate bits in the output lines. If a routine is fully enclosed in one rung, it is easier for others to follow. If you have to break it up into multiple rungs, it is a pain in the "A" as it is more difficult to have to go to a series of rungs using internal bits. It also takes up more memory and increases scan times.
beerchug

arnoob,

About 2 Outputs on the same ladder rung:

Parallel is Peachy,
Series could be Serious!

watch those parallels

SET MEMORY_LANE = ON

I remember back in the PLC 2 days.

You could enter up to 7 parallel branches when you were keying in your rung on your T3 terminal, and you could see most of it as you were typing.

However...
After you were online, you could only see the top 6, and the seventh one was hidden.

Nasty bug, eh

SET MEMORY_LANE 0 = OFF

I prefer to have multiple outputs on one rung when it makes intuitive sense to do so.

If I split the outputs up and have all the "dummy bits", inevidably sometime later someone else will come along and insert a bunch of rungs between the two related rungs, and before you know it other people are having difficulty troubleshooting.