Warning Light issues

[rubberboy]

I have 2 Plc's running 2 different production lines, both of which have a string of warning lights that pulse depending on the situation... The problem is I am constantly getting sticking outputs (or even blown outputs)from these modules d4-16tr and U05t... am i doing something wrong? 1 plc pulses these lights at 1 sec intervals while the other is 100ms... 405 - 450 plc... the lights amp output has been tested under the modules rated capacity...

[Controls Guy]

Well, regardless of rating, the lights are obviously not good for the outputs.  You may be looking at the maximum rating, which may not last as many cycles as you need.  Anything flashing, especially at 100ms is going to accumulate cycles fast.  If the lamps are DC, move the lights to a transistor output.  If the lamps are AC, you could try a solid state AC output module (usually a triac), but I really don't like them.  My personal experience has been better reliability with relay outputs than solid state when switching AC.  For AC lamps, I'd recommend a DC output driving a high cycle relay, perhaps solid state.  Even if you just use a generic plug-in relay, it will have much better rating than a PLC relay output, and will cost $5 to replace when it does eventually go bad.