Fault Finding - Motor circ/S-plan

[jonnymc11]

Hey all, did my am2 last week....

was so nervous, as i live on my nerves! couldnt even eat my breakfast on the days i went.

Passed my job, and testing, but i struggled and failed on the fault finding.

I work in the domestic enviroment, and managed to find the faults on my ring main, co2 circ, data.

Have any of yous had these faults? incase i get them again, so you's might be able to point me in the right direction, of where i went wrong perhaps?

I got two faults on my motor and 2 faults on my heating, which i could not find.

Fault - Motor: Motor will Not operate

So, I thought i might have an open circuit on the Line's, or Neutrals.

belled each on out, couldnt find a thing. Only thing i could not get a ring on was the incoming/outgoing neutral terminal in the DOL starter.

The supply line buzzed out, but when i went to the bottom it didnt, but i dont no if its supposed to with it not being energised?

Fault - Motor: Tenant complains on a tingling feeling when touching the dol starter and water pipe

belled everything out, but never used IR tester, possibly N-E you supply to dol starter inside the steel trunking you think?

Heating Faults

When calling for hot water the MCB trips

Boiler and pump continously running

both possibly shorts but could suss out where to test between.

 

[sparkytim]

Difficult to tell for sure but "sounds" like

Fault 1 Loss of nuetral continuity thru the starter

Fault 2 Loss of CPC continuity, with some leakage current, shock when touching extraneous metal work.

Fault 3

Hot water Zone valve faulty, Permanently stuck in on position (Giving permanent feed to boiler and pump from contact in Zone Valve)

AND

Possible water leakage into Zone valve causing MCB to trip when Hot water called for. ( Had this on yesterdays call out, only it was the RCD tripping)

 

[Doc Hudson]

ANDPossible water leakage into Zone valve causing MCB to trip when Hot water called for. ( Had this on yesterdays call out, only it was the RCD tripping)

Could that also be a burned out motor winding, short circuit, with as you say valve switch contacts jammed in on position?

Doc H.

 

[Larnacaman]

Fault - Motor: Motor will Not operate

So, I thought i might have an open circuit on the Line's, or Neutrals.

belled each on out, couldnt find a thing. Only thing i could not get a ring on was the incoming/outgoing neutral terminal in the DOL starter.

The supply line buzzed out, but when i went to the bottom it didnt, but i dont no if its supposed to with it not being energised?

If when you say '' lines'' do you mean a 3ph DOL motor?? ...If so then the neutral will be a direct connection to the operating coil. The other side of the coil will be the start/stop live through the holding contacts....

 

[jonnymc11]

Yes, 3 phase dol starter....

all of these are WIRING faults, not are the eqipment, cant be burnt out etc.....

7 wiring faults to find......

thank you

 

[retiredsparky]

Fault one: open cct feed to start switch inside DOL.

Fault two: open cct or high resistance in bonding.

Fault three: L/E fault on feed to circulator [pump].

Fault four: Motorized valve micro switch faulty.

 

[jonnymc11]

Fault one: open cct feed to start switch inside DOL. - what on one of the phase's or neutral? you only get a bell tester and IR tester, and they all rang out.

Fault two: open cct or high resistance in bonding. - that's what i thought, i used to bell tester and it buzzed, so did all the phases

Fault three: L/E fault on feed to circulator [pump]. possibly yeah

Fault four: Motorized valve micro switch faulty. - can only be wiring fault ONLY, they said, short, open, cross polarity's.

thank you very much

 

[oldtimespark]

jonnymc11 are the wireing diagrams not available to you when you do the fault finding .

Can you download the diagrams to the forum so they can be looked at.

Then advice can be given on fault finding methods but not the answers the person doing the fault finding must come to there own conclusions.

 

[retiredsparky]

Faults are: open cct, shortc cct, cross connection and high resistance. Use the meter on the ohm's setting not on the buzz.

1. usually feed to green button swtich.

2. keep meter on ohms should read 2.5 ohms for high resistance.

4. faulty valve yes you right no equipment faults only wiring, but orange and grey shorted would simulate a faulty micro switch within the valve.

 

[a1]

jonnymc11 are the wireing diagrams not available to you when you do the fault finding .Can you download the diagrams to the forum so they can be looked at.

Then advice can be given on fault finding methods but not the answers the person doing the fault finding must come to there own conclusions.

In bold, would be best.