Novamill intermittent sticks at S on startup...

[bpmsl]

Hi,
I'm looking for a little help on fault finding. Some times (usually after its been heavily used over the weekend and then left for a week) my novamill base unit boots and sits with the denstep display at S. The machine doesn't initiate and the gentle hissing noise from the mill doesn't occur.

It clears if you cycle the power a few times, so I'm assuming that (as its intermittent) its probably a sticking safety interlock relay as I understand that the S denotes an interlock is open, again assuming there is a relay. I'll admit I got lost in the circuit diagrammes availble on here.

Any thoughts?

Cheers
BPM

[Denford Admin]

S suggests that the machine is still in emergency stop.

Have a look under the front of the machine at the emergency stop switch and contacts.
I'd be tempted to link the emergency stop wires together and power back on just to see if the switch is the problem

[bpmsl]

Thanks Admin,
OK it appars that the switch isn't the problem... so is there a relay in the loop that could be sticking on power up?
Cheers
BPM

[Martin]

The 11pin ESR (Emergency Stop Relay) may have a faulty contact on it.
It may be worth checking if the ESR is energised when in the fault condition.
If it is then wires 58 & 59 should be closed circuit. It may be that you have a faulty contact on the plug in relay. If so you should be able to unplug the relay & clean the contacts.
If it is fitted with a Omron relay it should have a plastic pin on it that can be pressed in to test the outputs.

[bpmsl]

Thanks Martin.
Having given the relay switch a good wiggle to cycle the contacts a few dozen times i've not had a problem since, guess it was just a sticky relay or dirty contacts.

Cheers
Barry M