Motor focuser wiring.

[banjaxed]

I recently bought a 4Tronix remote focuser kit for my Skywatcher motor focuser which worked fine  until the motor ceased working. Before I sell the kit does anyone know if I could use another motor with this kit as the Skywatcher motor is connected with a plug with 4 wires whereas my motor only has 2.

Edited January 21, 2022 by banjaxed

[banjaxed]

I just tried to connect another motor to the Skywatcher controller using the same format, yellow/green to positive and red/black to negative and it does not work, has anyone got any suggestions?

[AstroKeith]

19 hours ago, banjaxed said:

I recently bought a 4Tronix remote focuser kit for my Skywatcher motor focuser which worked fine  until the motor ceased working. Before I sell the kit does anyone know if I could use another motor with this kit as the Skywatcher motor is connected with a plug with 4 wires whereas my motor only has 2.

4 wires will almost certainly be a bipolar stepper motor. 2 wires is a simple dc servo motor. Completely incompatible.

Your previous stopped working, but are you sure it was the motor and not the drive?

[banjaxed]

1 hour ago, AstroKeith said:

4 wires will almost certainly be a bipolar stepper motor. 2 wires is a simple dc servo motor. Completely incompatible.

Your previous stopped working, but are you sure it was the motor and not the drive?

Thank you for your reply. When I said the motor stopped working it still turns but it is not strong enough to turn  the focuser. When I first tried it a few weeks ago it was working fine but for some reason it has lost its power.

 

 

[AstroKeith]

That's weird. I can't imagine the motor has lost power. Is it the 4 wire or 2 wire motor that has lost power? If 4 wire it may have a lost one wire?

Is it struggling with the cold weather?

[banjaxed]

24 minutes ago, AstroKeith said:

That's weird. I can't imagine the motor has lost power. Is it the 4 wire or 2 wire motor that has lost power? If 4 wire it may have a lost one wire?

Is it struggling with the cold weather?

It is the original 4 wire Skywatcher motor which has suddenly lost its power and it has been indoors all the time I have been using it. It is a few years old now so maybe it has just worn out.

[AstroKeith]

Stepper motors don't wear out! I strongly suspect a wire broken/dodgy connection or driver output blown.

[banjaxed]

Thank you for your input, I will check the wiring but it is the same with the original controller as it is with the 4Tronix remote controller.

[AstroKeith]

If the two controllers connect to the motor via the same connector, then check that connector and the wiring to the motor, ie the common parts.

It could also be a burnt out coil in the stepper motor. Can you test the coil resistances?

Is there a part number on the motor?

[banjaxed]

It is the same connecting cable so I will test that it is ok. The motor has the following numbers. TJ-F00-1 and 190122 0397. I have a multi tester but I am not familiar with stepper motors wiring.

1 hour ago, AstroKeith said:

If the two controllers connect to the motor via the same connector, then check that connector and the wiring to the motor, ie the common parts.

It could also be a burnt out coil in the stepper motor. Can you test the coil resistances?

Is there a part number on the motor?

 

[Nigella Bryant]

Hi, my skywatcher stopped working and I took it apart and the cog from the motor to the drive cog's had slipped. Replaced in the same position and working perfectly again. I've had this go on both my skywatcher focus motor's. Might be worth taking a look. Easy enough to tack apart and refit. 

[banjaxed]

38 minutes ago, Nigella Bryant said:

Hi, my skywatcher stopped working and I took it apart and the cog from the motor to the drive cog's had slipped. Replaced in the same position and working perfectly again. I've had this go on both my skywatcher focus motor's. Might be worth taking a look. Easy enough to tack apart and refit. 

Thank you for your suggestion, I will certainly give that a try tomorrow, looks like it could be a good possibility 👍.

[banjaxed]

17 hours ago, Nigella Bryant said:

Hi, my skywatcher stopped working and I took it apart and the cog from the motor to the drive cog's had slipped. Replaced in the same position and working perfectly again. I've had this go on both my skywatcher focus motor's. Might be worth taking a look. Easy enough to tack apart and refit. 

I did as you suggested but everything seemed to me fine to me so I checked out the connections on the RJ11 plug an sockets and noticed 2 out of the four connections were a lot lower in both sockets and after lining them all up, hey presto the motor is working again.

[banjaxed]

20 hours ago, AstroKeith said:

If the two controllers connect to the motor via the same connector, then check that connector and the wiring to the motor, ie the common parts.

It could also be a burnt out coil in the stepper motor. Can you test the coil resistances?

Is there a part number on the motor?

As you will notice from my reply to Nigella it was the connections as you rightly pointed out. Thank you very much for your help, it is much appreciated.

[Nigella Bryant]

Great news, I've always said you have to be an electrician, engineer and IT specialist with this hobby, lol.