Trouble shooting?

[FrankUK]

I do a lot of commissioning and trouble shooting for a well known name of ventilation/heat recovery equipment, and I was tasked to have a look at a problem in Bournemouth today, where the fault was reported as an electrical heater 'overheat' problem.

The ventilation unit has an inbuilt supply fan and extract fan, heat exchanger and electric heater battery. The unit is 3 phase with inbuilt controller.

Here's the pictures of what I found. The additional wire terminals (not the manufacturers grey ones) have been fitted by the installing electrician, who has taken a supply to feed the orange relay which switches the additional ventilation fans on when the unit is running.

K1 is the contactor for the supply fan on full speed

Anyone spot what has happened?

 

[Knobhead]

The pictogram drawing is the biggest problem. Any Electrical Trainee thinks they can wire a powerstation with them, but hasn't a clue how or why it works!

 

[Darkwood]

Im stripping out a control unit for a cutting machine next week .... if you want to see a blantant dis-regard for safety and an accident waiting to happen il post some pics up ... it will make this control unit on here look like class A work.

It dosn't help when operators running the machine don't speak a word of the queens and when it breaks down first this they do is prod contactors and swap relays which has led to its ultimate demise and i refused to cali-fudge it back into operation.

 

[Stuuk1]

Stuuk1 ..... what was your other post on about... where is the Star/Delta timer or even the set up for star delta?

I had only had a very quick look and guessed it as I've seen it happen before, having looked at the drawing after, there isn't one lol

 

[Knobhead]

Im stripping out a control unit for a cutting machine next week .... if you want to see a blantant dis-regard for safety and an accident waiting to happen il post some pics up ... it will make this control unit on here look like class A work.

It dosn't help when operators running the machine don't speak a word of the queens and when it breaks down first this they do is prod contactors and swap relays which has led to its ultimate demise and i refused to cali-fudge it back into operation.

Be interesting to see. Thank god I've packed in now. 40 years of headaches caused by plant operators. (Except for 2 years as "Production Manager". I made the maintenance gangs life a misery!)