HEQ5 not powering up in cold/damp weather

[David Rawlins]

My HEQ5-R Pro mount delivered in November was working fine for a while but when the weather got really cold recently (~4 degrees or lower), the mount wouldn't power up properly - the red light didn't come on. This was with both a Lynx Astro 12V mains power supply (voltage steady at 12.2V) and a lithium 12V battery (delivering 13V at the time) with the SW supplied cable. I unplugged and reinserted the plugs in each case and wiggled them too - no difference. There seemed to be some voltage getting through as the SynScan wifi dongle LED was steady yellow (as opposed to green normally). But the mount was effectively dead.

The mount works fine when the temperature is warmer.

FLO organised a return but seem unable to reproduce the fault or diagnose what might be wrong.

Does anyone have an idea what is going on?

Thanks very much

David

[Dr_Ju_ju]

Pure supposition, but in cold weather as components differentially shrink, especially with some metal parts that are press held together inside a plastic shell, can some times 'grow apart' e.g. sockets, switches etc....

So I'd suggest when the problem occurs, remove the control panel and gently move each of the power wires etc, and even look to see if there are any 'dry'ish' joints on the connectors.    

[teoria_del_big_bang]

So are FLO sending a replacement mount or wanting to repair and return the same mount?

Diagnosing this issue could take sometime and might need the mount to be in sub zero temperatures for quite a while to let all the components soak and get to that temperature which may not be easy  without a large freezer (might be what FLO have tried).

It could be a component issue or a dry solder joint that is made worse at the very cold temperatures and components, solder contracting.
 

Steve

[David Rawlins]

Thanks very much, Julian and Steve. I had surmised the same - a dry joint somewhere.

FLO don't have the facility to test kit in the cold (it was only 4 degrees), apparently, and appear at a loss so they are offering a refund - should I just take them up on it or is there any merit in pressing them to look again at the circuit board?

I waited 3 months for this one to arrive so am reluctant to start all over again sourcing another mount

David

[Carbon Brush]

You have not said how the retailer has tried to reproduce the fault.
Hopefully they have done somethingl ike the process described below.

In my work, when we want to test cold performance, we chill the item.
Often to -25C and work up from there.

In this case there is an easy fault description. Won't start when cold.

The obvious starting point is to duplicate reported fault situation.

Using a bit of masking tape, fasten a thermocouple or other temperature monitor to the mount.
Nothing clever. The £9.99 thermometers with probes from ebay and the like are good enough.
Wrap the mount in a poly bag with the thermometer wire and 12V power wire exposed. Leave it in a domestic deep freeze for a couple of hours.

Take it out and quickly wrap it in bubble wrap to slow warming.
Turn on the mount for a couple of seconds. If it does not start, turn it off again so there is no localised heating to skew findings.
Note your (knwn good) power supply is at room temperature and you have the opprotunity to measure current consumption in the 12V line, which may help in fault diagnosis.

If the bench test is done with the mount in bubble wrap, the slow warming is going to give uniform slow warming through the mount.
The time allows you to retry the test as the mount slowly warms and observe without rushing.

If you find the mount needs (for example) 0C to resume working, it is my opinion not fit for purpose, or has a fault.
If you find the mount comes to life at say -5C, it is more than a bit 'iffy' for UK use.

The test described does not need speciailist equipment. A domestic freezer is an everyday item. A thermometer with probe is commonplace and easy to obtain if you don't have one.
An ammeter to check current is very much an 'optional extra'.

As an end user, it is not really your problem to discover why the mount doesn't work when cold. It should work.
The test that hopefully FLO are doing demonstrates whether customer has given a reproducible fault descripyion.

If it doesn't work to -30C, fair enough for UK use. But SW (and others) do not to the best of my knowlede make temperate/cold/really cold variants of scopes and mounts.
They should work out of the box, whether in Alaska or Saudi Arabia.

HTH, David.

 

[PeterCPC]

Take the refund. You may never really get to the bottom of this and it will be very frustrating.

[Carbon Brush]

+1 to @peterCPC. Grab the money and run!

Did you realise Skywatcher do not publish a temperature range in their product manual?
Actually the manual I looked at didn't even give min/max voltages!

They aren't alone in this sort of omission.

If you go back say 20 years, there was hardly any electronics on scopes.
Today almost everyone wants a goto mount. Then a camera or two, then the control computer..........

Are all the equipment builder making product that it good for sub zero use?

David.

 

[teoria_del_big_bang]

It probably is fixable and if I had bought cheap 2nd hand is what I would be doing but if new I would take the refund.
I know its a pita when you have waited so long bot its a large chunk of cash so not worth the risk.
If you intend to use at some stage for imaging you want it to be reliable and to be assured once left in a sequence then clouds permitting it will work through the night, clear nights are precious in UK 🙂 
Also I think I misread your OP and thought you said minus 4 degrees but I think it is saying approximately 4 degrees isn't it, s if that's a positive 4 degrees then not really even that cold.

So Up to you but FLO are good and if they are being honest and saying they cannot test so the refund may be the best option

Steve

[David Rawlins]

Thanks, everyone.

FLO have made it clear they can't/won't go down the freezer route. Yes, it was approx 4 degrees that it stopped working and I bought it specifically for imaging so that isn't acceptable.

Peter, I think you are right in avoiding the hassle of endless back and to with FLO - I think I'll ask for a replacement/refund. I'm sure there's nothing wrong with SW mounts in general, just this one!

David

[FLO]

2 hours ago, teoria_del_big_bang said:

Also I think I misread your OP and thought you said minus 4 degrees

We thought the same ☺️

Initially when @David Rawlins contacted us he reported the problem only occurred when using the PSU. When using the original cable and car battery it worked okay. This is why we focused on power and replacing the PSU. He later said it stopped working regardless of how it was powered so we arranged collection and tested it in our workshop. We tried multiple power sources and all worked. Then the conversation centred around low temperature. My colleagues in the workshop involved me when they felt David had lost faith in the mount and was growing frustrated with it and us. We have learned over the years when this happens (no fault found and customer unhappy) it is often best if we simply refund in full. So I emailed David offering him a full refund. This is when he sought opinion from you good people 🙂 

@Carbon Brush You clearly work in this field so know your onions. I think it is time we bought a freezer for the workshop. 

HTH, 

Steve 

[FLO]

PS: Welcome to SGL @David Rawlins 🙂 

[johninderby]

A walk in freezer perhaps? 😁

 

Edited January 31, 2022 by johninderby

[FLO]

Will need a notice on the door saying 'No ready-meals or pizzas!' 😁 

[johninderby]

Just call it a cold weather test chamber for tax purposes. 😁

Edited January 31, 2022 by johninderby

[lenscap]

As said +4 Celsius isn't cold in astro terms but @David Rawlins did you notice any dew on the set-up when the fault occurred?

I had an intermittent electrical fault on an old car. It was fine in the dry but went into "limp-mode" whenever it rained, then was ok as soon as the sun came out. Moisture (from road splash) was partially earthing a 12v line which had a tiny area of damaged insulation, pulling the voltage low enough for the ECU to disable the circuit.

So if I was  diagnosing your mount I would be trying to provoke the fault with a water-spray bottle (not near any mains voltage of course) and seeing if it was cured with a hair drier. If so I would be looking for any damaged insulation, bent connectors or clumsy soldering that might provide an opportunity for dew-assisted earth leakage.

[Carbon Brush]

@FLO. Yes getting accurate fault descriptions can be a problem.
We (like you I'm sure) even have to explain sometimes that 'not working' is not a fault description🤣.

Ref Environmental test chambers - to use the posh words.

We use a domestic freezer and it takes us to -25C🥶. Adequate for most purposes.

A domestic fridge is fine for just over 0C type of checks. Subject to negotiating sandwich and milk space with colleagues.
Temperature remains remarkably steady (even after door opening) if you put lots of plastic milk bottles full of water in there.

For higher temperature work, we did though have to spend on a lab oven as domestic ovens are not stable.
Ours will go accurately from room temperature to 300C with controlled ramp up/down, temperature cycling, etc. with 😄bells and whistles.
It also warms pies quite well.

 

[malc-c]

I would have thought that seeing these mounts are designed to be used outside they would use internal components rated for temperatures likely experienced in most countries.  OK -40c in parts of Russia might be pushing it, but -10c to +40c would be a fair range.  I would therefore suspect that the problem is either condensation / dampness forming inside the mount and creating a shorting.  There could be a dry joint that contracts in cold temperatures, but you would expect that to happen well below freezing rather than +4c.   

A cheaper option to a walk in freezer for testing would be a cooling spray,  giving it a quick blast on the power port, daughter board and main board...taking care not to thermally shock the components.

Top marks to FLO in offering a full refund, even though in testing no fault was found...  That's customer service for you.

[FLO]

David says he prefers a replacement, not refund, so that is what will be arranged 🙂 

After we have frozen his mount in a fridge/freezer it will be added with reduced price to the Clearance board.  

Steve 

[Mr Spock]

Most electronics are not directly affected by cold. It's usually components shrinking or lubricants stiffening which cause a greater drain on power. You can also get condensation issues moving from warm to cold atmospheres.
I've never had issues with cold or moving from hot to cold with Skywatcher mounts, and I've had quite a few. The EQ5 I have now works well sub zero, and the EQ6 I had previously worked well at -7° straight from 22°.

Probably just bad luck to get one that's a bit flakey. It happens.

[Alien 13]

I would doubt any electronics including mounts are designed to be used outside, no sealed connectors. no conformal coating, no sealed nitrogen purged cavities with external heat exchangers etc, most items survive because they produce enough heat to keep the damp away.

Alan 

[malc-c]

1 hour ago, Alien 13 said:

I would doubt any electronics including mounts are designed to be used outside,

How else are you going to see the stars....  you ideally need to take the mount outside to use it.... granted they are not designed to be permanently housed outside and exposed to the elements, but should be able to take a bit of moisture from dew forming in during an observing / imaging session

[Alien 13]

28 minutes ago, malc-c said:

How else are you going to see the stars....  you ideally need to take the mount outside to use it.... granted they are not designed to be permanently housed outside and exposed to the elements, but should be able to take a bit of moisture from dew forming in during an observing / imaging session

Dont worry, most kit is engineered well enough to survive the UK climate.

Alan

[David Rawlins]

Thanks again to all who contributed to this. And to Steve at FLO for being so accommodating.

David