MC Chatter / Programming error?

[TerryRWood 0]

I have an application where my Motor Contactors (MC) occasionally "chatter" either on startup or shut down, and it seems to be program related. By this I mean... I am using a VB interface running on a AB VersaView 1500P/WIN XP with a SLC 503, all the MC rungs are basically the same, a NC (XIO) stop, followed by a NO (XIC) start, followed by a MC coil output (OTE), the NO AUX (XIC) contact on the MC is in parallel with the NO (XIC) start for latching. The problem can be reproduced by toggling the start/stop buttons, within about 6-8 toggles the MC gets hung in a loop of turning off and on really fast, probably equivalent to the scan time. Sometimes it occurs during the On cycle, sometimes during the Off cycle. Some have suggested this is an Active X issue. Processor details 1747-L532E 16K mem 12 program files 17 data files 2843 instruction words used - 1486 data table Any ideas appreciated

[jstolaruk 9]

Try putting a one shot instruction just after the bit that is being activated by the ActiveX control.

[gravitar 3]

In the past, I've taken the OTE off the rung with a chattering output and replaced it with a short-duration timer. The timer done bit is used to energize the output.

[jhorejs 0]

Ooooooppps, I thought this post dealt with a rap artist - MC Chatter!