Cable for a GX16-7

[cjdawson]

Hi all.

I need a little help making sure that I get the right cable.      What I’m looking for is a 7 core cable that can be used to connect two GX16-7 plugs.   I’m after something that will be helped properly by the cable restraint.    I’m ok with there being an 8th core if that makes thing easier.

Just not sure what cable to use.     The cores will be used to run a stepper motor, and a temp sensor.

[Dr_Ju_ju]

RS & Farnell, both do 7\8 core cables that will do what you want, at a cost.

But as you want to pass heavy current, stepper drive and, at the other end, sensitive temperature data, I'd recommend you look for multi twisted pair cables, to cut down on the cross-talk....

[cjdawson]

looks like AWG 20 7 core cable will do the job.   It's got an outer diameter of 6.5mm, so I should be able to squeeze that into the plug and have the clamp hold.

 

This is what I'm thinking of

https://uk.farnell.com/alpha-wire/1896-7c-sl005/cable-ul2509-20awg-7-core-30-5m/dp/1619543

[Dr_Ju_ju]

You can try, but I'd be worried about crosstalk from the stepper drives, to the temperature sensor, as none of it, is twisted pair (which reduces the crosstalk see transmission line theory) 

[cjdawson]

17 hours ago, Dr_Ju_ju said:

You can try, but I'd be worried about crosstalk from the stepper drives, to the temperature sensor, as none of it, is twisted pair (which reduces the crosstalk see transmission line theory) 

Can you link a better cable?

[cjdawson]

You know what, just been thinking about this.  I'm sure that I'll be ok with the cable that I linked.   why?  well that's quite simple really.  The motor will only be running when there's a need to move the focusser.  It will be powered down at other times, as I won't need to have the motor hold the focusser in place. (An advantage of an SCT).   So with that in mind, the stepper cables will be idle most of the time and the temp readings will only be an issue between focusser moves.