Electrical/electronics question

[GazOC]

hi all,

Last week I had a bit of trouble with the Meade DS motors on my CG5, they would slew at any speed from x2 to x128 but thaey would not move at x1. I was powering them from my 'Aldi special' powerstation. I'm now running them from the mains and the x1 tracking is fine.

Does this make sense electronically? That the powerstaion is supplying enough power to move the mount at x128 OK but not consistantly enough to track at a constant x1?

GAz

[weareborg]

Your best bet, would be to check out the Roboscope Yahoo group. (unless you have done already, in which case, please ignore this stupid suggestion. )

Andy

[Grant]

Gaz, it does make sense from an electronics standpoint, it seems like your powerpack isn't quite providing enough juice that the motors expect, is the powerpack a big car battery type thing? If so, have you tried it when the battery is fully freshly charged to see if that makes a different?

[Greg]

You need to measure the amps output from the powerpack under load at different slew speeds - the current draw should be the same - if not your motors are pulling too much ampage from the power pack.

These motors work on very low amps at 12v - it could be that the power pack once it drops below 11.5v it's not quite enough juice to drive the slow slew but ok for the faster slew. I've known battery packs to show 12v but no amps! Also with lead acid batteries keep them charged up all the time as once they get fully discharged the plates become sulphated and you need a special bit of kit to revive them.

Or could be a sign of the battery on it's way out - perhaps, not holding a full charge??

Greg

[Greg]

Gaz - I take it you'll be bringing it to the SP - if so i'll bring my meter and Optmate - if ther's a fault with the battery pack my machine will find it!!

Greg

[GazOC]

Greg,

Thanks for the offer mate but I've got it round a friends house who's an Intruments Technician and he's prodding and poking around with it for me!!

With those batteries are you supposed to fully recharge them after every use? I've just been doing it when the level lights were getting low?

I fugured it was the powerpacks fault, it's just the slew thing puzzled me, I'm glad to know I havn't defied the laws of physics!!

Gaz

[Greg]

Gaz - if it's a lead/acid battery then it should be topped up after every use, preferably before the lights come on (As a car battery) They are designed to be "Trickle" charged all the time.

Greg