Dave,

Without knowing the switch type, it is hard to be 100% sure, but I think you have a 3-pole switch (1 to 2, 3 to 4, 5 to 6). This fits with your labelling, connecting live and neutral to the motor, but the connections to 3 and 4 are a bit harder to identify. I cannot identify the green operating 'unit' – according to Danfoss, this could be undervoltage or overcurrent protection, or even a separate auxiliary 'add-on' contact. If it is a 3-pole switch, then the connection from 3, through the green start button, and the loop 2-4 do not seem to be strictly necessary, and the switch would work simply by pressing the 'hatched' bar.

Sorry if this is confusing – this is why I strongly suggest looking for a type number on the switch. If you search for it on the Danfoss site, nearly all their products have a downloadable PDF tech sheet, which shows connection details.

Failing that, they also have a technical assistance department to answer online queries about their products – even an expert would need technical details to correctly identify connections.

hi dave,

usualy these starters are modular in design, contactor, start button, and overload with the stop button. they usualy use the same numbering system for the electrical conections. are there any numbers/letters on the terminals of the start stop switch? your diagramme does not appear to have an overload unit, what is the power rating of the motor?

If that switch were contactor.

1 — 2

3 — 4

5— 6

where are the armature connections ?

think of thing as large relay.

normally wired so one contact set powers "coil" with green push button( NO) wired in parralel abd red opush button in series (NC)

{reaches for pen to make sketch….}

Hi wotsit,

I suspect even Danfos will not be able to help without a model number. I suspect either of us could sort it out in a few minutes with the item in front of us.

Les.

Are there any safety interlocks or cut outs fitted to this machine, i.e. a locking emergency stop button which might be holding the control circuit off?

By following this link there is a 28 page Danfoss technical data sheet available for the range of contactors which includes the CI-9, this would probably help an Electrician sort things out.

Danfoss link

Edited By V8Eng on 25/04/2012 19:44:58

Edited By V8Eng on 25/04/2012 19:46:02

Some emergency stop buttons lock in when pushed and need twisting or some similar action or even a key to release them.

Hope this is not teaching granny to suck eggs, but did you operate the reset before trying anything else?

Edited By V8Eng on 25/04/2012 19:52:46

Hi, Dave,

Apperently there is a CI 9 three pole contact breaker made by Danfoss (not C19). There is a connection diagram in their documentation Here

You can download the PDF User Guide (last document in the list of 4) This contains a circuit diagram of the switch, although it does not seem to correspond exactly to what you have described. The unit at the side appears to be a Thermal overload trip.

Perhaps you can take a look at it, and see if it corresponds to your switch. I would disconnect the connections to Terminals 3 (connection to Start button) and 4 (the loop) of the main switch. This should leave you with a simple switch, operated by your hatched bar. If that seems OK, then the User guide should help you to reconnect the thermal overload.

As Les Jones said earlier, it looks as though somehow it has been connected so as to put the supply voltage directly across the thermal switch hence your sparks and smoke. Any information you have would help – can you post a sketch of the connections between switch and motor? Did the green 'Start' button ever work? Did anything happen at the time it stopped working – and most important – has anyone 'fixed' it since it failed (and maybe changed a connection! )

The basic unit is not a switch, its a 3 pole contactor. Its got a coil to actuate it (NOT the hashed button) or there would be nothing to hold it in. So turn the thing on its side and find two contacts sticking out of the coil, which also will have the operating voltage on it. If the operating voltage is 230V, then it can be wired from the mains live to one side of the coil via the normally closed "off" contacts. The other side of the coil goes to the incoming mains neutral. So now, pushing the green button should put mains on the coil which pulls in the armature and switches the mains through to the motor. Releasing the green button should allow the armature to drop out and the motor stops. Not quite what you want!, so anoth set of the main contacts is wired to the mains on the input side, and the output side is wired to the junction of the ON switch and the OFF switch.

Now when you press the N switch the contactor pulls in and routes mains to the coil so releasing the ON switch has no effect. Pressing the OFF switch breaks the supply to the coil, so the armature drops out and every thing stops.

If you have the thermal over loads then the switch/ contacts from them is simply in series with the coil, so its like another OFF switch .

Frank