Intermatic Pool Timer Wiring

[BigDave]

... I may have a licensed pool technician check the wiring ...

Please have a licensed electrician with pool experience look at your wiring. Pool guys are not electricians. Please.

[Pappy]

Has it been verified that the pump is wired for 120v rather than240v?

[sjeffers01]

I did check it for obstruction and there wasn't anything, I am not sure about diffuser but I will check it. The pump is really quiet. No screeching or whining.

[PoolDoc]

@Pappy: pumps wired 120v but fed 240v can die fairly spectacularly . . . but they don't run for awhile and then shut off. I'm not sure I've seen a pump wired 240v and fed 120v, but I'm guessing it would just hum till it overheated.

[Pappy]

Years ago, when I did plant maintenance, I got a job at a place that had just fired a guy for sub-standard work. They had 240v chain hoists that the man had wired one leg direct, meaning one leg at the fuse box was run through the fuse and the other leg was TOTALLY unswitched. One of the supply cables got pinched and shorted the protected leg. The fuse blew, but the wire welded to the steel trusswork. The guy running the hoist had his back to the fireworks, and didn't hear anything because of the plant noise. The hoist slowed WAY down and fried after a few seconds. After that happened I got to looking at the wiring, and there was ALL kinds of stuff that he had done that way. I haven't done that kind of work in MANY years and motors have changed alot since the early 80's but it might be worth looking at.

[mas985]

In both the under-voltage and over-voltage case, an induction motor will draw excessive current so it is a matter of what fails first. Either the breaker will trip, which usually happens in most cases or the motor will heat up very quickly and trip the thermal limiter or the winding's will melt. In all cases, the motor will either not run at all or run for just a few seconds before failing. But it won't run for minutes and it won't pump water.

http://www.motorsanddrives.com/cowern/motorterms12.html

[Pappy]

Thanks for the info.

@Mark, your signature says you have a .5hp 2 speed pump. What make/model is it? Or did you put it together from individual components?

[mas985]

I put it together with a 1/2 HP Northstar wet end and a 2 speed motor.

[sjeffers01]

Sorry about delayed response. I was out of town. I checked the pump and it is wired for 120V. The pump still works. It takes about 1/2 HR. before it gets hot enough to shut off when it runs during the early morning hours. I will have an electrician look instead of a pool guy but I really don't think the wiring is the problem. I took a picture of the pump wiring.

[sjeffers01]

I forgot to correct the 120V to 115V. I found the manufacturer date for the pump. It is 06/18/2005. I wish I found out sooner. This pump's 9th birthday is getting close and the overheating problem is likely due to its age. I might as well use it until it quits. The suction and expulsion are really strong and it keeps my pool pretty clean. I am having a Home Performance review next week and that could include a recommendation on replacing my pool pump. I would get a rebate or low interest financing through SMUD. I will close this thread since we now know the Intermatic Timer was working correctly and the pump is old and needs to be replaced with an energy efficient dual speed pump. To those of you who responded, thank you for taking the time to help me out. I have learned a lot and am now too scared to mess with the electrical stuff. You probably saved my life.