Elta fan controller problems

[brizospark]

I am having some problems with an Elat variable speed 3 phase fan controller which I have installed in a restaurant.

The speed controller (149-TC33) is rated at max peak current 3A and the fan that is being controlled runs at 2.9 amp according to the manual.

Fan is also Elta (SMC560/4-5-3) and this setup was recommended by Elta. The problem is that the speed controller transformer has burned out after a few hours. I was very apprehensive at installing the 3A rated controller given that the running current of fan is so close at 2.9. I did clamp meter all three phases which were sitting at around 2.7 - 2.8.

Should this fan be controlled by the higher rated (5A) controller or should this setup have been ok?

 

[snowhead]

If Elta say it should be OK and it wasn't it's for them to sort it out, as in supply the correct controller F.O.C

 

[brizospark]

Would you also reckon that a 3 amp peak current supply is a bit on the shy side for a fan running at 2.8A?

 

[brizospark]

Anyone?

 

[Marvo]

According to Elta's website spec sheets the transformer speed controller was correctly specified. You did right to clamp all three phases and the run currents sound good. I'm not personally familiar with the specific fan or speed control so I have a couple of questions; did the fan have 2 thermistor wires in the motor terminal box? Did you connect them? Also what overload/missing phase protection does the circuit have?

 

[brizospark]

The fan did not have any facility for thermal overload and I have provided an overload at 4a in the DOL starter

 

[Sintra]

Is the fan connected delta or star?

 

[brizospark]

Fan connected delta

 

[Marvo]

When you say the speed controller burned out can you be more specific about the damage? Maybe post a photo or two if there was anything that could be seen as damaged.

From what you've said I don't see any reason it would have gone toes-up. Most common causes of failure would include incompatible speed controller, incorrect wiring, phase failure, poor terminations and reverse rotation. From your test results and statements none of these stand out as particularly likely as nearly all of them would show up as high run currents.

 

[FrankUK]

Fan connected delta

Why would you connect a 3amp fan to run delta....unless of course the manufacturer recommends it.

 

[Marvo]

The fan is a 400v 4 pole 3-phase motor, delta is the correct connection scheme.

 

[brizospark]

Just clamped the amperage again. When running on speed 5 (full) the run current is 3a but when I adjust to speed 3 the current settles about 5a is this normal? And if not what would cause this?

 

[brizospark]

Drop in voltage rise in current I presume

 

[brizospark]

Turns out should have been a 5A supply there was a printing error in Elta catalogue!!!

 

[Marvo]

Serious??? That could turn out to be an expensive printing error for them. I assume they're happy to give you a warranty replacement.