Denford Software & Machines

so you should have the 0-10v variable voltage on 4 and 6, with 4 being positive. If you're not getting any voltage on 4 and 6 and you've specified a speed and commanded a spindle start on the triac, this will probably be the fault. Pin 5 should have a reference voltage on it, so check across 5 and 6 for 10v. If you get 10v across 5 and 6, remove the wires from 4 and 6 and connect 4 and 5 together, then you should get full speed when you command a spindle start.

Again be careful here as the 0v of the 0-10v is not connected to ground.

Hi,

I have been out and tested for those voltages.

I have no variable 0-10Vdc between 4 and 6.

There is also nothing between 5 and 6, so I presume that the reference voltage is missing, and thus causing the fault?

Is this voltage fused somewhere?

Thanks again
Paul

You could always fit a potentiometer to the 3 connections (I'm sure the manual I referred to earlier shows the speed input as a pot)
Then you'll know for sure that's the issue.

I had thought about a pot, but if the reference voltage is not there, surely that wont work?

thanks
Paul

Ah yes sorry - I hadn't seen you mention the reference voltage was missing.
I'd certainly expect 10V between two of the speed input pins (5 and 6, Lo and Hi according to the B&P manual)

Try it again with the wires disconnected from 4,5 and 6...

Ok,
I have tested the voltages with the wires disconnected, and between pins 4 and 5 I get approximately 7.8Vdc when spindle speed was set at 1000rpm. It then steadily decreased until the machine faulted out.
When I connect the wires back on, the voltage is not there.
I am guessing that this is what you expected to happen?
Any ideas why?
Here is a pic of the terminals on the fanning strip.
I really appreciate the help guys

there is one other thing to try on the fanning strip.

You can manually run the spindle by removing the wires from 4, 6, 7, 8 and 9.

Then get a PP3 9v battery and connect it up to 4 (+) and 6 (-). and take 8 and 9 to a switch. Turn on the triac and close the switch, this should give you near full speed.

PS. have you removed the jumper wire you put on the main contact strip.?

Hi angel-tech,

Thanks for the reply.

I have just tried that, and still nothing at all. Does tis mean that I need to look for a replacement Brown&Pestell drive because this one is caput?

Cheers
Paul

one of these will do

https://www.ebay.co.uk/itm/380382624135? ... 1438.l2649