Spitting - help with HEQ5

[MishMich]

Background.

2 months ago bought a 2nd hand HEQ5. Got the hang of using an EQ mount. Over Xmas, ordered a Synscan upgrade. When the cloud settled in after the first week in Jan, I upgraded the mount. Tested it indoors - seemed to work fine. Two weeks indoors followed, enforced by cloud.

Ten days ago, it looked cloudless and promising, but by the time it was all set up, clouds had rolled over. Left the scope etc. outside to cool down. Went back out, things were damp, still cloudy, but plugged in the power pack - and the mount was dead. Put everything away, charged power pack, JIC. Next day, tried it again indoors, everything seemed to be working OK. Another week of cloud saw me update the firmware, set up ASCOM & EQDIR & checked connectivity & function with Stellarium, and PHD connectivity, and so on.

Then a few days ago, there was a break in the cloud again, and I set everything up, and managed to do a basic alignment as the clouds appeared to the west, and managed to get off some farmes of Mars to test the QHY5 worked. Everything seemed to be running fine. More cloud, more testing indoors, setting up GPS & QHY connectivity through ASCOM.

So, tonight was clear but poor - very bright moon, hazy, couldn't make out many stars, but figured that things might improve, and there was enough to check out the alignment, and connectivity through the laptop, possibly even test out the QHY5. Got it all set up, left it to cool down for an hour (scope sits in a cool oubuilding anyway). Everything started off OK, but when I set the scope to do an alignment it was making this awful sound. Then zilch. Switched it off, and tried again - same thing, it would start with a grinding noise, sometimes stop, sometimes slew smoothly, then grind to a halt. When it stopped, nothing would happen till I reset it. Then I noticed the power tank was showing amber. Odd, I've hardly used it in a week or so since I last charged it.

Swapped the tank for a 12v mains adapter. Same thing.

Any ideas? Does this mean stripping down the gears and re-regreasing is called for? Or is this the motors? It seems odd that it grinds to a halt, then there is no response to the handset. One or two times, I switched the handset off and on, and I gould move the scope in one axis, but no response in the other. I tried flipping the scope over to the other side of the mount - same problem.

Is this the effect of cold & damp air on the motors? Loose connections? I am spitting - the only redeeming thing was that the seeing was too poor to do much anyway, but it would have been nice to have had the time to get to try out the new kit, instead of the mount just grinding to halt like that.

When I tested alignment in my living room, it had no problem aligning with where I figured Sirius would be. When I tried it outside, it was all over the place.

M.

[Merlin66]

Mish,

When you apply the power to the Synscan handcontroller on its own ( disconnected from the mount) does it fire up OK?

I don't think you could be so unlucky to have blown the motors or control board??!!

[Ibbo!]

I could be way off here

the cold could be playing havoc with the power pack

and

is the 12v adaptor pushing enough current

sorry if you have checked

[MishMich]

The handcontroller fires up OK. I just took the drive cogs out, and tried it. There is a clunk, and then just a buzzing sound. Then the handset goes dimmer. Then it doesn't respond to commands. Apart from the initial 'clunk' when it tries to engage, there is no movement at all.

I guess I need to get on to FLO and get it back to them. What a pain. I don't understand why it worked indoors, but seizes up outside. I don't see how the motors could have blown - I've hardly used it. I always check the balance. I've checked the connections - they seem solid.

M.

[Ibbo!]

Sounds like not enough umph

Check the current requirements of the mount and the power supply

some of the wall wart type P/S are low current rated

[MishMich]

Yes - I tried a more powerful mains adapter, and that works. Phew! Thanks. I was getting worried.

I guess the Synscan motors must draw a lot more power than the Nexstar SLT or the non-Synscan HEQ5, and with them the tank didn't need charging more than once a week. Even so, I've hardly used it since I charged it a week ago. I was using the cigar-plug lead that came with the Synscan, but its not very long - I'll see if I can use the one that came with the power pack, as that one lets me run off the power pack while it's indoors. It must be below zero outside, the OTA was lined with ice. Maybe the power packs don't work very well in the cold?

Thanks for the help. I'll put it back together, and check it out properly again when the tank's charged up.

M.

[dark knight]

Funnily enough I think I've seized mine too......only mine wont turn in DEC axis even with the clutches undone......typical...

M, I think synscan draws 7 amps, at least mine does which is (was) eq5 with synscan......

[Merlin66]

I have the HEQ5pro Synscan and it only draws about 2.0 -2.5A

Those PowerTanks are a PITA!!

You should seriously think about going to 20Ah gel cells and a decent triple stage electronic battery charger ( Search on gel cell to see ALL the other threads on the subject).

Ken

[dark knight]

Mines on mains and transformer so enough power can't be the problem. Looks like a complete strip down of the mount is in order to check the dec assembly doh...

[MishMich]

Power Supply: 11 to 15 V DC 2Amp

Power Tank is rated as 7 Ah - so I guess that would translate to 3 1/2 hours of use, and I doubt I've used it anywhere near that much. Only four months old. I guess I'll need to invest in a more powerful mains adapter - and save the power tank for camping trips. Or nip down to a building suppliers or motor-spares store and get one of those all-singing dancing jobbies.

:-) then I can have the pleasure of saying 'I tild you so, I should have got one of them when I saw them in the shop a few months back.

In hindsight I'm not surprised - the way that Synscan moves the scope. I don't move it as fast as that manually.

Feeling much better - a good lesson to learn on a poor night. Was worried the motor's were fried (but couldn't see how they could be).

M.

[MishMich]

Thanks for the help folks. Not sure what is going on with the power tank - it took all night to charge, and it didn't take more than a few hours before. Plugged in the scope earlier this morning, and there was a 'pop' and a puff of smoke came out. Switched it off, waited a while, tried it again - seems to work OK again, slewing via the paddle buttons anyway.

I spoke to FLO, and they said I can send it back, or wait and see how it checks out. Had a bit of a chat, and am very impressed with their philosophy - and am pretty sure if FLO stock what i want, I'll not be looking any further in future.

M.

[Cornelius Varley]

Did the "pop and smoke" come out of the powertank or mount ?

Peter

[MishMich]

Sorry - it came out of the mount. It looked like it was from one of the motors, rather than the board, although at the time the word 'capacitor' went through my head... It smelled a bit like burned grease. I'm wondering if a blob of grease from the cogs might have worked its way into the motor?

FLO say there are usually only a couple of things that can have problems - one is with the handset, the other is the power connector, which can cut out in the cold, and involves a fiddle to ensure the

terminals connect properly. They've not heard of this before. I was wondering if there's a short-circuit somewhere - which might also account for the tank draining unexpectedly. I checked all the connections when I opened it up, and they are all firm.

M.

[adamsp123]

Dimming handset when mount is plugged in = maybe a short circuit, smoke almost certainly equals something fried/short circuited.

[Ibbo!]

If the magic smoke has escaped I would return it

Steve

[Glider]

My HEQ5 draws 2A when tracking. A battery will go flat quicker when it is cold. 7Ah only equates to less than 3.5 hours use. Your 'average' 12Vdc wall cube might only supply 1A, is it regulated or unregulated? Did the polarity of the connection to the mount centre pin get reversed by accident?

Pop and smoke sounds bad.

[MishMich]

I'm not sure I can face taking it apart and sending the bits back - I just know the minute I do, the skies will clear...

M.

[MishMich]

Such a frustrating hobby.

M.

[dark knight]

Those power tanks are utter garbage, had mine on charge for over a week and it still didn't indicate it was charged...

[MishMich]

I looked at a hundred pound jobbie that could double-up for use with the Bongo auto-sleeper we use for camping. Not too worried about the 240v inversion or compressor, which left two 12 v sockets, light, jump-starter. Nowhere said what the output rating was, apart from for jump start, and only indication of how long it would run was based on a chiller or a spot light - no A/h figure. So, it could end up being no better, just more features I don't need, and a lot more money.

I saw somehere that did a 12v bench transformer somewhere, with 3 or 4 lighter sockets, which would be more useful for home use, but can't remember where.

Tried out the HEQ5 again earlier while it was still light outside, to test out the QHY5 in daylight (nice sharp images, confirmed it is monochrome); mount seems fine (apart from the whizzy noise when starting & stopping slewing - which it has done all along) using the paddle keys - although I couldn't test out alignment & GoTo slewing, or control from laptop. Would have carried on when it got dark, but for rain and cloud (yawn - how long can it go on like this?).

M.

[dark knight]

how about one of these

15A 13.8V Bench Top Power Supply Unit

You then just need one of these, just cut the plug end off and connect the wires to the above power supply terminals and hey presto 3 sockets at your disposal.

Triple Cigarette Lighter Socket adapter with attractive LED

[MishMich]

Oh, thanks. I just revived a thread about this to ask exactly that question. I have a single lighter-socket with red & black conncting leads, I'll attach that, and use the 1->3 adapter I also have and plug that in to that. It seems about the same. I just prefer electricity tucked away inside boxes and cables where I can't see it ...

M.

[dark knight]

Yep I know what you mean M. I house all mine then inside a large tuppaware box with a tight fitting lid, the box has holes in the sides for the cables to pass through. This stops any dew or moisture getting on the sockets. Can't be too careful.

[arad85]

@glider - are you sure that's 2A whilst tracking The power supply has to be rated at 2A, but that doesn't mean the current drain will be constant at 2A, just that it needs to be capable of supplying it.

Having said that, don't skimp on power supplies for the mount. I've read of people who have had problems with the handsets & control boards which were seemingly caused by failing power supplies. I ended up building my own based around a 105Ah leisure battery (I have mains power in the garden, but wanted something truly portable - I intend to try some dark sky imaging once I'm a bit more practiced). See: http://stargazerslounge.com/diy-astronomer/95646-105ah-powertank.html

[dph1nm]

There seems to be some disupte about the current draw. I have seen some people claim 2A continuously and some claim only 2A when slewing - and they all claim to have measured it!

Certainly my 7Ah power pack won't drive my HEQ5 for more than an hour or so (I believe that you should only use these packs to ~half their rated value - so a 7Ah battery will only give about ~3Ah in reality). Mind you, my Skywatcher 17Ah pack never used to last much longer (fairly dead now) - still, it came free with the GOTO upgrade so I can't really complain!

NigelM