extractor fan electrical install help needed!

[finyuk2005]

I have gotten a hold of a monster centrifugal fan to use as extraction on my plasma table, it used to be used for grain drying.
Its a 5hp 3 phase motor run off a "Stayrite Single Phase Power Drive"

I did get it to work a few times, but most the time it doesnt come up to speed and often trips the breaker, ( I do need to have the supply from the house to the shed upgraded!)

Just wondered if anyone knew anything about these setups?
Its been sat unused for many years, i wondered if new capacitors would help, but im not sure where to find the correct ones

cheers!

 

[Welderpaul]

From my experience with these things, the capacitor has always been the fault.

If you have a tester can you check their values? A blow out and a check for loose/broken conductors would be worthwhile.

 

[finyuk2005]

From my experience with these things, the capacitor has always been the fault.

If you have a tester can you check their values? A blow out and a check for loose/broken conductors would be worthwhile.

Ah good idea, my multi meter should be able to test that i think,
I did notice one of the caps was a fair bit warmer than the other after just a few attempts at starting,
Also the caps are different ratings by the labels, but they are wired in parallel to the same terminals?

I was trying to upload a video showing a start attempt but havent figured out how to do that yet!

 

[finyuk2005]

From my experience with these things, the capacitor has always been the fault.

If you have a tester can you check their values? A blow out and a check for loose/broken conductors would be worthwhile.

How would you read the farad ratings on those caps? 90-115 on one and 150-190 on the other, im just not sure what i need to search for to find an equivalent

 

[finyuk2005]

a video of a start attempt

 

[Onoff]

Can you measure the startup current with a clamp meter?

Exactly what trips, the "breaker" feeding the shed or local "breaker" feeding the Power Drive etc?

Might be that the inrush current is tripping the breaker. Changing from a Type B to C or D may work.

 

[Agroshield]

The Stayrite Power Drive is likely a static phase converter. That might give you a wider term on which to search or to find circuit diagrams.

Some of them had a manual 'boost' switch on them for heavy starting loads.

 

[m_c]

A 5hp motor is going to need quite a big single phase supply to start it without tripping anything.
However given it came off a grain plant, there is the possibility that it's designed for 415V single phase (might have been a slightly different voltage!), as some remoter farms only had split phase supplies, and not full 3 phase, which would explain why they used a phase converter and didn't just run it from 3 phase.

Personally I'd power it with a VFD, as then you'd get some control over how much extraction you get.

 

[wyn]

I used a fair bit of farm stuff where you had to start it with a lever in one position then move it to another once it was up to speed.
Star to delta or the other way round or something along those lines.

 

[finyuk2005]

Can you measure the startup current with a clamp meter?

Exactly what trips, the "breaker" feeding the shed or local "breaker" feeding the Power Drive etc?

Might be that the inrush current is tripping the breaker. Changing from a Type B to C or D may work.

My shed is only supplied from a 32A mcb and its usually the one that trips, i need to get it sorted properly, like an isolator straight from the henley blocks or something
I will try my clamp meter on it indeed, that would be interesting! its bound to have a pretty massive starting current!

 

[finyuk2005]

A 5hp motor is going to need quite a big single phase supply to start it without tripping anything.
However given it came off a grain plant, there is the possibility that it's designed for 415V single phase (might have been a slightly different voltage!), as some remoter farms only had split phase supplies, and not full 3 phase, which would explain why they used a phase converter and didn't just run it from 3 phase.

Personally I'd power it with a VFD, as then you'd get some control over how much extraction you get.

it is a monster of a motor anyway!
I think it was always run off 240v single phase
If i can get the stayrite thing to work it would be fine, a 5hp vfd would be dear enough i would think

 

[finyuk2005]

I used a fair bit of farm stuff where you had to start it with a lever in one position then move it to another once it was up to speed.
Star to delta or the other way round or something along those lines.

It seems like its doing something like that, when it works it gets up to a certain speed, when it stops accelerating I let go of the start button, and then it ramped up to a faster final speed

 

[finyuk2005]

Actually a VFD even that size isnt too deadly! I have a few of the cheap 2ishKw ones and they work fine,

4.4KW VFD Drive Inverter VFD Inverter 4kw Brake Resistor 220V AC Single Phase Variable Frequency Drive Inverter VFD Speed Controller Inverter For 3 Phase Motor : Amazon.co.uk: Business, Industry & Science

4.4KW VFD Drive Inverter VFD Inverter 4kw Brake Resistor 220V AC Single Phase Variable Frequency Drive Inverter VFD Speed Controller Inverter For 3 Phase Motor : Amazon.co.uk: Business, Industry & Science

www.amazon.co.uk