Motor Starts

[SteveG]

I was curious about how some of you guys handle simple motor logic. I've been doing this for some time now but would like to hear your opinions. To keep this post managable lets start with this criteria:

Motor : Single Speed, FWD/REV
Operator inerface : FWD, REV, Stop, Tag Out, Clear Tag Out
Inputs : FWD AUX and REV AUX
Outputs: FWD and REV (Both maintained)
Permissives: 1 per direction
General Alarms : Fail to Start FWD and REV, Fail to Stop FWD and REV; Congruency Alarm (both feedback true).

These are my usual alarms, please let me know any others that you use. I've seen plenty of "Standard Logics", but I'm convinced that all of them can be improved.

If this is too basic, we can try servos, but I'd like to start simple.

Thanks,
Steve

[Rick Densing]

I am not familiar with the "tag out" term, but everything else mirrors what I do. Without spending more money, what else is there? Maybe an accumulated run time for the motor. This would require someone to reset it.

[Allen Nelson]

SteveG:
Your list is incomplete:

Mode: Auto/Man/Off Local/Remote Jog(each direction)
Interlock: 1 (or more) per direction;
Bypass Interlock Command (each direction)
Acknowledge (each alarm you listed) individually.

Ok, I guess you're "Tag Out" is the equivalent of "Off Mode".

I don't have any "standard" way of doing it, because every project is unique. In general, I have one (or more) "Status words" and one "Command word" for each motor, , and I'll use the same bit number in the word for that state across the entire project (Bit 0 = Auto, Bit 1 = Man, etc).
That't the key - be consistant.

Beyond that, I don't think that I do anything special that you won't find in PLC Programming 101.