Automatic transfer switch surge protector blown!

[mrrkspark]

Hi all

I installed an 80kVa diesel generator set with automatic transfer switch awhile ago. All supplied by customer.
Generator is second hand at 50 hours work and it turns out the ATS is too.

All has been working fine for the last 6 months or so but recently the generator has been struggling to get up to 50 hertz in the set time. It has been taking around 4 or 5 attempts to crank too.

Recently the customer tried it on test mode, to put it under load, and the surge protector inside the ATS went out with a big bang and has completed fried causing a hell of a lot of smoke!

Is this likely to be a problem with the generator, or with the monitoring equipment within the ATS, or a bit of both?

 

[shanky887614]

Hi all

I installed an 80kVa diesel generator set with automatic transfer switch awhile ago. All supplied by customer.
Generator is second hand at 50 hours work and it turns out the ATS is too.

All has been working fine for the last 6 months or so but recently the generator has been struggling to get up to 50 hertz in the set time. It has been taking around 4 or 5 attempts to crank too.

Recently the customer tried it on test mode, to put it under load, and the surge protector inside the ATS went out with a big bang and has completed fried causing a hell of a lot of smoke!

Is this likely to be a problem with the generator, or with the monitoring equipment within the ATS, or a bit of both?

it will probably be worth getting a genny company in to assess the job, it will probably be cheaper to get them to have a look and service it as well

 

[guest119]

Is it starting from cold or has it got a crankcase heater?

 

[davesparks]

When was the engine last serviced?
When was/is it due?
As far as taking 4/5 attempts at cranking to get it to start goes it is going to be the same as any Diesel engine really. Bad/gone off diesel, knackered glow plugs, failing lift pump, partially blocked fuel filter, failing starter motor, weak battery, the list is pretty expansive

 

[Engineer54]

Hi all

I installed an 80kVa diesel generator set with automatic transfer switch awhile ago. All supplied by customer.
Generator is second hand at 50 hours work and it turns out the ATS is too.

All has been working fine for the last 6 months or so but recently the generator has been struggling to get up to 50 hertz in the set time. It has been taking around 4 or 5 attempts to crank too.

Recently the customer tried it on test mode, to put it under load, and the surge protector inside the ATS went out with a big bang and has completed fried causing a hell of a lot of smoke!

Is this likely to be a problem with the generator, or with the monitoring equipment within the ATS, or a bit of both?

From the little you have told us here, we couldn't start to diagnose any specific problems.

You say that this genset has been installed for 6 months, what is the average loading this generator is supplying, and how many hours has it run in those 6 months?? Has ANY maintenance been carried out during that time?? Why were the surge protector(s) located in the Transfer switch

What sort of earthing arrangement did you provide at the time of installation, and the tested values?

 

[mrrkspark]

Thanks for your reply's.

I believe it does have an engine heater.
No maintenance has been carried out as far as I am aware and it has not been run much at all. Possibly 5 times for 15 minutes each at around 20 amps load.

The ATS was supplied with the generator with the surge protector already wired into it.

The installation is TN-C-S but an earth pin was installed for the generator at a value of about 80 ohms and the generator had a neutral earth link fitted already.

Are there any common causes for surge protectors to blow like that? It was as the generator tried switching in to take the load.
I assumed it was because it wasn't up to frequency and something faulty in the ATS let it switch over?

 

[Deleted member 26818]

Does it have a manual change over option?
Are the phases in sync?

 

[mrrkspark]

Is single phase and doesn't run in parallel with the grid.
It has the settings on the ATS for

off - mains power only
Auto - Generator stand by
Manuel - Fire generator but no changeover
Test - Fire generator and changeover

 

[Knobhead]

Single phase? Thats just short of 350A! Seems a strange setup to me.

 

[mrrkspark]

I do apologise, my mistake it is 80 amps single phase

 

[Knobhead]

18KVA makes a bit more sense.