Help on fault finding on a C3-31 Hammer combination machine

[EddyCurrent]

You should test a supply in both no load conditions and with a load of a significant percentage of that with which you are having problems.

No desire to be pedantic about this but,
That's not what I meant about 'rule no1' , I meant if there was nothing there when you pressed "start". In other words, "check there is the required voltage at the machine".
The quality of the supply comes later after pressing "start" does it's job.

[OMLCNC]

Sorry but I made a mistake when testing the voltage on the transformer, wrong connections.
Now get readings of 464v and 260v.
Also get 242v over the contactor.

What to check next?

[m_c]

What happens to the voltages while the motors are starting, and the contactor chattering?

[OMLCNC]

What happens to the voltages while the motors are starting, and the contactor chattering?

From putting the meter over A1, A2 on the contactor and pressing the start button the voltage is not instant ie it climbs to 240v while it chatters,
same if you put it over any of the other contacts. When it pulls in it is 240v. So readings might be 50, 70, 130, 170 then 240v (all while chattering)

Is there a way of wiring out the braking board item 7 on the drawing and still making the machine work to eliminate it from being the problem?
I can disconnect wire 24 from the contactor to stop it breaking, but there are 5 other wires still connected.

Then I can happily spend the £500 knowing that that is the cause.

[EddyCurrent]

Testing is not proceeding in a logical manner.

Personally, I would install the original contactor first.
With the machine disconnected from supply, manually operate the contactor and confirm, using an ohmmeter, that all the contacts operate as expected.
Then I would remove the load, i.e. disconnect the selected motor, e.g. saw
Plug the machine in and press start and see if the contactor pulls in and holds
Now with a voltmeter I would test to see if we are getting 3 phases (full voltage) at the disconnected motor leads.
If not, I would start at the supply end and work my way through to find the reason.
If yes, then it suggests the wiring and contacts are okay, on no load at least.
If you then press stop, there should be DC across 2 of the motor wires for several seconds (it makes a loud humming noise under normal conditions)

If your machine works in a similar way to mine, if an e/stop button is pressed and you press 'start', then the braking system energises for several seconds just as during a normal stop.
This means that if the contactor, and it's contacts, are not working correctly it may be possible to initiate the brake during startup. This is the main reason
I would refit the original contactor and auxilliary as there may be some time delay involved here.
The drawing is one of the worst I've seen and it's not easy, for me anyway, to determine exactly what's going on, and I've used some complex drawing in the past.

I've attached a copy of the single phase version if it helps sort this out, (not studied it yet though)

[OMLCNC]

Testing is not proceeding in a logical manner.

Personally, I would install the original contactor first.
With the machine disconnected from supply, manually operate the contactor and confirm, using an ohmmeter, that all the contacts operate as expected.

No they do not.

(1 and 2) and (3 and 4) closed all the time (NO) even if you manually opperate contactor.
ONLY when Planer and Spindle Moulder selected.

When Saw selected all contacts operate as expected.

Plug the machine in and press start and see if the contactor pulls in and holds
Now with a voltmeter I would test to see if we are getting 3 phases (full voltage) at the disconnected motor leads.

Yes it pulls in and holds.
Yes 440v - 460v out of three wires at plug to motor.

Does this point to item 10 the selector switch?
The Saw does not operate correctly all the time, it still makes the contactors chatter.
If that helps.

If you then press stop, there should be DC across 2 of the motor wires for several seconds (it makes a loud humming noise under normal conditions)

If your machine works in a similar way to mine, if an e/stop button is pressed and you press 'start', then the braking system energises for several seconds just as during a normal stop.
This means that if the contactor, and it's contacts, are not working correctly it may be possible to initiate the brake during startup. This is the main reason
I would refit the original contactor and auxiliary as there may be some time delay involved here.
The drawing is one of the worst I've seen and it's not easy, for me anyway, to determine exactly what's going on, and I've used some complex drawing in the past.

I've attached a copy of the single phase version if it helps sort this out, (not studied it yet though)

Yes I get the loud humming noise when I stop the machine.
Here is a picture of the original contacts and auxiliary, I've split them apart so you can see the information.
I can not see that they have a 1 second delay, can you?

[m_c]

From putting the meter over A1, A2 on the contactor and pressing the start button the voltage is not instant ie it climbs to 240v while it chatters,
same if you put it over any of the other contacts. When it pulls in it is 240v. So readings might be 50, 70, 130, 170 then 240v (all while chattering)

Is there a way of wiring out the braking board item 7 on the drawing and still making the machine work to eliminate it from being the problem?
I can disconnect wire 24 from the contactor to stop it breaking, but there are 5 other wires still connected.

Then I can happily spend the £500 knowing that that is the cause.

The readings are what I suspected you'd get, especially with a multimeter.
What about the input voltage to the transformer?
If they also drop, what about the main supply into the machine?


What I can't really make out from the wiring diagram, is are the top right wires, and lower left side wires on the braking module directly connected (I'm guessing each wire has a separate terminal, but are the terminals paired together? - A photo might help)

However, I think if you remove the link between R8 and 4 on the contactor, it'll be enough to break the circuit for the braking.
Do you have a diagram for the selector switch, as it would help understand exactly what's going on?

Assuming the selector switch is just a switch, with no relays/contactors to control things, then the key to the braking circuit is how the 3rd leg is handled. It is controlled via the auxiliary contact (other two legs go via the main contacts, with the third main contact used as the latch for the start button - the start button second contact also bypasses the aux. contact, which I assume also ensures the braking module remain inactive until the contactor is fully energised), but goes to the braking module, before heading to the selector switch, unlike the other two legs that go straight to the selector switch.
The braking module is also connected to the 2nd leg output from the contactor (terminal 4), via the NC contact (R8), so when the contactor is energised, the braking circuit is broken, but once the contactor is de-energised, the braking module is connected to the 2nd and 3rd legs on the motor side. By breaking the 4/R8 link, it should prevent the module from braking (which I'm assuming is done either via DC injection braking, or controlled shorting of the legs).

[OMLCNC]

The readings are what I suspected you'd get, especially with a multimeter.
What about the input voltage to the transformer?
If they also drop, what about the main supply into the machine?


What I can't really make out from the wiring diagram, is are the top right wires, and lower left side wires on the braking module directly connected (I'm guessing each wire has a separate terminal, but are the terminals paired together? - A photo might help)

However, I think if you remove the link between R8 and 4 on the contactor, it'll be enough to break the circuit for the braking.
Do you have a diagram for the selector switch, as it would help understand exactly what's going on?

Assuming the selector switch is just a switch, with no relays/contactors to control things, then the key to the braking circuit is how the 3rd leg is handled. It is controlled via the auxiliary contact (other two legs go via the main contacts, with the third main contact used as the latch for the start button - the start button second contact also bypasses the aux. contact, which I assume also ensures the braking module remain inactive until the contactor is fully energised), but goes to the braking module, before heading to the selector switch, unlike the other two legs that go straight to the selector switch.
The braking module is also connected to the 2nd leg output from the contactor (terminal 4), via the NC contact (R8), so when the contactor is energised, the braking circuit is broken, but once the contactor is de-energised, the braking module is connected to the 2nd and 3rd legs on the motor side. By breaking the 4/R8 link, it should prevent the module from braking (which I'm assuming is done either via DC injection braking, or controlled shorting of the legs).

See pictures - Yes the wires are connected on the PCB board, paired together as you thought, I checked them with "the tester"
Other red wire goes to 24 and brown to R7

Also see pictures of rotary switch, you may be able to work out how it works. It could be the issue if you see my other post to Mr Eddycurrant

[EddyCurrent]

This is the brake unit I think; http://www.klibo.com/brake_16a.html?L=1
and there are drawings etc.

[magicniner]

No desire to be pedantic about this but,
That's not what I meant about 'rule no1' , I meant if there was nothing there when you pressed "start". In other words, "check there is the required voltage at the machine".
The quality of the supply comes later after pressing "start" does it's job.

If I'd been referring to your suggestions I'd have quoted you.
When looking for the source of a fault in a 3 phase electrical system where components such relays and actuators are commonly run from one phase with different components running from different phases then if you don't check what you have before applying any load at all then you can make things harder for yourself.
Just saying ;-)