Extractor issues

[LBCarpentry]

I have a 3 phase JET double extractor in need of help (possibly the bin)

On firing her up, instead of the instant and positively aggressive startup to let you know she’s ready to rumble, there’s now a slow and gradual startup and seems like it’s only running at around 70% - 80%. Happens intermittently but becoming more frequent.

have had the extractor for a good few years now working hard with zero maintenance.

Anyone have any ideas? These things are basically very simply motors turning a fan.

Many thanks!

Louis

 

[mindthatwhatouch]

Could be electrical fault, low voltage, loose connection.
What kind of starter have you got?

Possibly mechanical, so motor bearings, will the impellor spin freely if turned by hand, impellor damage causing unbalance or dust build up, (that’s an easy check)

start with the simple stuff, are ducts, filters, motor etc in need of a clean. Do you have the ability (happy to) put a multimeter on the motor?

 

[Argus]

Unless there's an obvious mechanical or bearing issue stopping it getting to work, it sounds as if you have a phase missing somewhere, either on the incoming feed, in the contactor itself or one of the windings open circuit.
That motor will, in all probability, be star wound. As it is a fan it is starting without load and although capable of turning on two phases, there will be a serious loss of power/speed and a likely increase of residual heat in the windings.
If you suspect that it is electrical, you'll need a reliable meter and a logical end to end test.
It's the first thing that I'd eliminate.

 

[LBCarpentry]

Hhhhmm the fact that I’ve been using the isolator to switch it on and off could have easily knocked a connection off.
Shall investigate

 

[Argus]

Hhhhmm the fact that I’ve been using the isolator to switch it on and off could have easily knocked a connection off.
Shall investigate

That's where I'd start....... new isolator.

3 Phase switches don't take kindly to that sort of thing on a regular basis. It's not the starting that causes damage - it's the full-load-current arc when you break the circuit. Cooks 'em to death.
It's only money!

Good luck

 

[LBCarpentry]

I think it’s deffo my abuse of the isolator switches. Found some lose connections already. Shall report back

 

[LBCarpentry]

Sorted. One of the phase wires was loose and arching in a fuse box. Nice burnt cable and melty plastic. Sorted now thanks everyone!

Louis

 

[Jester129]

Looks like you avoided the arrow with that one then.