Noisy,buzzing contractor

[cliffed]

Changing contactor,this one clatters & buzzing.
Will put a report in,can you see the red 2.5m single cable,this comes off the LIVE side of the contactor,control for this circuit.
The Mccb protection for this circuit,which supplies a TPN DB rated @ 200 amps.
Any ideas how to protect this control circuit.

 

[Pete999]

Changing contactor,this one clatters & buzzing.
Will put a report in,can you see the red 2.5m single cable,this comes off the LIVE side of the contactor,control for this circuit.
The Mccb protection for this circuit,which supplies a TPN DB rated @ 200 amps.
Any ideas how to protect this control circuit.

Slide lock fuse and carrier, fitted in the contactor control circuit.

 

[Vortigern]

I have cleaned up contactor faces before now and reduced or eliminated chattering, it is possible.

 

[Steviec1]

You will need to find out what the control circuit is supplying to figure out the size of fuse/circuit breaker to fit, a double pole one will be needed to switch both live and neutral

 

[Pete999]

You will need to find out what the control circuit is supplying to figure out the size of fuse/circuit breaker to fit, a double pole one will be needed to switch both live and neutral

Why DP? May be a 400v control circuit no N, unlikely but has been known

 

[Steviec1]

Looking at the picture, there are 2 wires from L1 and N.
Not sure what the control circuit is feeding. I presume that at it is 3 phase it will be industrial.
In my opinion breaking live and neutral together is safer.

 

[cliffed]

Looking at the picture, there are 2 wires from L1 and N.
Not sure what the control circuit is feeding. I presume that at it is 3 phase it will be industrial.
In my opinion breaking live and neutral together is safer.

It’s 230v ctrl not sure yet what it’s doing.
Still abit naughty coming off LIVE like that.

 

[Steviec1]

It’s 230v ctrl not sure yet what it’s doing.
Still abit naughty coming off LIVE like that.

I think the control cables should be closer to the size of the main cables feeding in.
That would be a better practice

 

[littlespark]

When the title says “noisy contractor” I was expecting a joiner that talks too much.?

 

[telectrix]

i once had excessive chattering bashing my lugholes. i divorced her.

 

[DefyG]

Cant tell if the contactor is Din Rail mounted but if it is I'd put a MCB (3A?) alongside it.

 

[DefyG]

contractor

Predictive text !!!!!

 

[loz2754]

Predictive text !!!!!

Defective sext

 

[Pete999]

I think the control cables should be closer to the size of the main cables feeding in.
That would be a better practice

The control circuit has lower consumption therefor a smaller cable suitably fused down should be employed, sorry for the red cross by the way, if it's a large load say for example fed by 10mm cable are you suggesting using 10mm cable for the control circuit as well?

 

[Pete999]

I think the control cables should be closer to the size of the main cables feeding in.
That would be a better practice

I think the control cables should be closer to the size of the main cables feeding in.
That would be a better practice

A silly practice I think Steviec 1:

 

[Pete999]

I think the control cables should be closer to the size of the main cables feeding in.
That would be a better practice

Sorry for the disagree red cross Mate, but a main circuit sized conductor for the control circuitry, apart from be unnecessary is impracticable, have you ever tried getting main circuit sized conductors, say above 2.5mm2 cable into the coil/pushbuttons etc terminals?

 

[Steviec1]

The control circuit has lower consumption therefor a smaller cable suitably fused down should be employed, sorry for the red cross by the way, if it's a large load say for example fed by 10mm cable are you suggesting using 10mm cable for the control circuit as well

A silly practice I think Steviec 1:

The control circuit has lower consumption therefor a smaller cable suitably fused down should be employed, sorry for the red cross by the way, if it's a large load say for example fed by 10mm cable are you suggesting using 10mm cable for the control circuit as well?

Not at all,imagine f a fault developed at the point where the main cable enters the isolator/contactor. If the main cable is 25mm and the control cable is 2.5mm, there is a danger that the smaller cable could suffer "burn out". This could result in a fire!!
The control feed at this point should ideally be the same or at least 50% of the size of the main cable until it reaches the circuit breaker or fuse for the control circuit.
Of course ideally the cables of dissimilar size could be fed from a busbar system and bolted seperately, this would negate the problem.

 

[Pete999]

Not at all,imagine f a fault developed at the point where the main cable enters the isolator/contactor. If the main cable is 25mm and the control cable is 2.5mm, there is a danger that the smaller cable could suffer "burn out". This could result in a fire!!
The control feed at this point should ideally be the same or at least 50% of the size of the main cable until it reaches the circuit breaker or fuse for the control circuit.
Of course ideally the cables of dissimilar size could be fed from a busbar system and bolted seperately, this would negate the problem.

Only if the fuse /mcb didn't operate

 

[Steviec1]

Only if the fuse /mcb didn't operate one should always use best practice

 

[Steviec1]

One should always use best practice