Low Voltage on HEQ5 with Flashing Lights - Lead or PowerTank?

[PhotoGav]

Hello All,

I have been suffering the dreaded flashing red light on my HEQ5 Pro mount, being powered by a Skywatcher 7Ah Power Tank and using the standard 12V cable supplied with the mount. This has just started happening the last couple of uses and seems to tie in with ambient temperatures being much lower, around 5 degrees. I don't think it happens straight away, but after 40 minutes or so. The handset reading was around 10.6V.

So, I set everything up in the sitting room yesterday and the light was steady, with a voltage reading of 12.3V. This was maintained for over an hour and a half.

My next line of investigation is to set up outside in the cold and see what happens. I will power the mount from the car 12V outlet and see if that changes things. Hopefully that will eliminate the cable as the culprit. If it does, time to buy a new power source. My investigations lead me to a Maplin yellow jump-starter box.

If the mount still doesn't function correctly from the car power, I can point the finger at the cable. So, the question is this:

Can anyone reccommend a really tough cable to replace it with please?

I look forward to your responses.

Thanks,

Gav.

[Uplooker]

I have had similar issues with  a Maplins Jump Starter pack and my NEQ6. It was due to the low voltage from the power pack. the cold does really affect the performance. How many nights usage between charges do you get, 7 Ah is not a lot of capacity.

Ian

[peroni]

I had this issue with my Maplins 7Ah pack. When I used it on cold nights the pack would drain very quickly. 

I fixed the problem by putting the battery pack in an old laptop bag. The bag was padded and so provided some insulation to keep things a bit warmer.

As my scope is only used in the back garden, I moved over to use the Maplins mains supply. No running out of power anymore. 

[peroni]

I really should read the whole post before replying 

FLO provide replacement power cables. I have one now and it is more secure and thicker than the original cable that came with the mount.

[Tinker1947]

If you can change to a Mains powered supply, the Maplin 7amp work fine and will take a 20m lead so it in the dry just  a low voltage cable to attract the dew ect....FLO sell them as well as Maplin....

[PhotoGav]

Thanks for your advice folks.

Peroni - you may have the ultimate answer with a 'battery cosy' for those cold winter nights!

Cheers,

Gav.

[Tinker1947]

Thanks for your advice folks.

Peroni - you may have the ultimate answer with a 'battery cosy' for those cold winter nights!

Cheers,

Gav.

You will get the flashing light from batteries / powertankis ect the stated voltage on the Skywatcher site is 11 - 15 Volts a fresh battery might last a short while but slewing, GoTo ect will suffer over the course of a viewing session...

[jambouk]

I'm running off a home made mains power supply using a laptop power source with 15v, 6 amp output, and it is working a treat, but my mount accepts 11-16v apparently.

James

[Tinker1947]

I'm running off a home made mains power supply using a laptop power source with 15v, 6 amp output, and it is working a treat, but my mount accepts 11-16v apparently.

James

The AZ-EQ6 takes 11-16volt @ 5 amps, i doubt one of these would perform to well on a Powertank ect and remain accurate with the GoTo....

[Carl Reade]

Hi, 7Ah is nowhere near enongh to run the mount in my opinion. Yes the cold will effect the battery. The most worrying part is the reading of 10.6 Volts if the battery has went to that level it is effectivly dead or damaged.

Carl

[PhotoGav]

Hi Carl,

Thank you for that pretty drastic diagnosis! I think you may well be correct though... So, the question becomes: what is the best portable power pack for this mount? I can't power from the mains as my best observing site is in the middle of nowhere!

Thanks,

Gav.

[Carl Reade]

Sorry to be so drastic lol, What I would do is work out what Amps you will be using on all your kit then buy a battery that is rated at the highest Ah you can carry, the higher the rating the heavier it will be.

Ulimatimatley I would recommend a 100Ah leisure battery but they are heavy it would run your scope for years if looked after.

 If you had say a 20Ah battery and were drawing constant 5 Amps in theory you would be able to run for 4 hours but in the real world 3 would be better without totally draining it as that is a real battery killer.

Hopefully helpful Carl

[jambouk]

I've run the mount alone on my halfords 17amp/hour pack all night with no problems. If you are using anything else which draws current you'll have problems.

I recently got a "dead" 45 amp /hour cat battery for free from my mot garage, which has charged up nicely and holds it well; if you are not going to deep discharge the battery that would be a cheap option, but unlike leisure batteries cat batteries don't like deep discharges.

James

[Steve Ward]

I had exactly the same thing with my HEQ5Pro running off the SW 7Ah tank , when I checked the voltage after an hour it had dropped to 10.4V , I switched to using a Mains powered supply and have had no troubles since.

The 7Ah tank is woefully short in performance in the winter months when the temperature starts to get down low .

I know that a mains supply is of no use to those of you that travel to remote locations , but for home use they are a godsend ( until the power goes off that is ...   )

[PhotoGav]

Carl, it's getting technical now and I struggle with things electric, so I hope that you will be able to help me... I've got the HEQ5 Pro mount and a HitecAstro single-channel, dual-port Dew Controller, with one dew strap attached. From what I can glean, the HEQ5 Pro is drawing 2-Amps and the dew controller is drawing 6-Amps, though this is a combined figure, so can I call it half for one dew strap, i.e. 3-Amps? Here are my sources for these figures:

Mount: http://ca.skywatcher.com/_english/02_mounts/02_detail.php?sid=59

Dew-Controller: http://www.firstlightoptics.com/dew-prevention/hitecastro-single-channel-dual-port-dew-controller.html

Do you agree with the Amp figures?

If so, that means the draw is 5 amps, which would give me about an hour and twenty minutes of power from the 7Ah tank.

If that's correct, it's not surprising that the light is flashing after an hour or so........

Time to make yet another equipment upgrade!

[Carl Reade]

Thats exactly it Gav. You can now see why your battery is lasting a short time. It is that easy. The Ah rating just means that is the max the battery can supply for one hour before being drained.

So if you had a 100Ah battery and your full 5 amps being drawn it would last for 20 Hours  before recharging in theory. When I say in theory I mean you wouldnt let it go to full drain which isnt good.

Car battery: Is designed to give 100s of amps for a short period of time to start a car but not designed for slow continous draw, hence if you leave your lights on it goes flat. After it starts the car it is immediatly charged by the alternator at up to 30 amps. Although it will work for a while on the mount.

Leisure battery: Is designed for slow amp draw, hence its use in caravans for lights and TVs etc. It has larger plates inside to cope with this. It can be charged 100s of times if looked after.

You can also get a golf cart battery which is also a deep cycle type you could use I think they are smaller than the leisure type. (also designed for slow discharge)

I think the more power you have if out remote the better

Hope that helps

Carl

[PhotoGav]

Thanks for taking the time to help me out Carl. I've taken drastic action to solve this one and have ordered a 75Ah leisure battery, with battery box and charger. Hopefully that will knock the flashing red light on the head!

New equipment = cloudy skies, so I apologise for the inevitable lack of clear skies over the next few nights...!

Cheers,

Gav.

[PhotoGav]

A little update...

NO MORE FLASHING RED LIGHT - Hurrrraaaahhhhhh!!!!

So, I tried the power tank wrapped up in a coat in a bag, but the power output still dropped right down and the light flashed. Binned that one.

Tonight, I have been using the new 75Ah leisure battery in its box and that little red light is glowing solidly and has been for quite a while now. I guess I must be up to about three hours use now. So, definitely a power tank issue and nothing to do with the cable.

The set-up is busy exposing subs of M45, fingers crossed that my framing is good and that the tracking gives me some useful frames! Isn't it fantastic to have a clear sky at last. Hopefully it will be worth waiting for the moon to set and the results will make me smile!

Thanks for the advice all and my advice from this is: don't bother with the skywatcher 7Ah power tank...

More clear skies.

Gav.