HEQ5 Pro Mount Stopped Working - Need some advice!

[Xiga]

Hi guys!

 

Well, while I was out recently trying to shoot NGC 7000, I ran into a pretty serious problem.

 

I have a 3 or 4 yr old HEQ5 Pro (Orion Sirius in the states) and i did the Rowan Belt Mod about a year ago. It's been working really well for me since, i and i usually get great guiding. Well, on this occasion, after i powered everything on, i could smell something burning, so i quickly turned everything off until i could find what it was. Turns out, it was the EQDIR cable, which had a hole melted right through it! The laptop is fine though, no damage done to any of the USB ports.

 

I can still power on the mount, the red light comes on and if i connect the Synscan hand controller i can slew the mount in RA just fine. However, i can't slew at all in Dec. There isn't even a sound as though it is trying. What's more, as soon as i press either the Up or Down arrow on the hand controller, nothing else will then work, not even slewing in RA. It's as though it's crashed, and only power cycling will let me slew in RA again (I can also scroll through all the handset's settings, and I’ve tried doing a factory reset but it didn’t change anything). Also, while the mount is powered on, if I plug in the old fried EQDIR cable into the mount, but leave it open at the other end, i.e not plugged into the laptop, then as soon as it clicks into place the red power led on the mount starts flashing really quickly. When I unplug it, it goes back to being solid. If I plug in the hand controller the light doesn’t flash at all, it stays solid.

 

I opened up the mount and had a good look around. The Dec motor cabling is definitely connected (i re-seated it just to be sure). If i rotate the cog & pulley, the mount does move in Dec, so the gear is definitely engaged. I did think it felt a little stiff when i undid the clutches and tried to rotate the mount in Dec, but not so much that it would cause it to not work. I tried loosening & tightening all sorts of screws but to no avail. It's almost as though the Dec motor has given up the ghost entirely (although apparently that’s virtually unheard of).  

 

Note, i'm using the celestron 7ah lithium power tank to power the mount alone. The laptop and DSLR just run off their internal batteries. I like the lithium battery as it’s small & light, can be run down to near empty without issues, and is more than enough to give me a full night of imaging considering the mount uses very little power while tracking.

I should also mention, up until about 9 months ago I used to power the mount from a celestron 17Ahr power tank, but after going through a couple of power cables (suspiciously since i did the belt mod) i switched to the Lithium battery and i've had no problems ever since. I suspect i may have done something when i did the belt mod, but i know next to nothing about electronics or mounts, i simply followed the instructions to the letter and it seemed to work ok. I now only use the 17 Ahr power tank just for my dew heaters.

 

I heard back from the guys at FLO, who I ordered the mount from originally. They seem to think that it’s the motherboard that has gone, so I’ve ordered a new one, along with a new EQDIR cable (according to the engineer at FLO's supplier, the Control Panel board either works or it doesn't, so it's unlikely that it is the reason). I hadn’t properly considered the motherboard to be the problem tbh, as I can still power on the mount and slew just fine in RA. I thought if the board was gone then the whole thing would just be completely dead.

 

Does anyone have any input/experiences with an issue such as this? Does this sound familiar at all? The motherboard arrived today but without any instructions at all. Having done the belt mod before, I am at least somewhat familiar with the insides of the mount, but I would still have liked some instructions. Having looked online, the best I could find are the pictures I’ve attached below that come with the Synscan Upgrade Kit for a basic EQ5 Mount, but if anyone has anything better I’d love to see it.

 

One last thing, ever since doing the Rowan belt mod, when I screw on the big plastic spacer that comes with it (to raise everything up over the cogs & pulleys) I always had a small gap left over no matter how hard I tightened the screws (see the picture below). Could this small gap have been enough to let moisture get in during cold weather, and could that have led to the problems I’ve had? I might try and insert something that’s thin and malleable, yet not porous, in the gap before I screw the bracket back on next time, in the hope I can keep any moisture out. Anyone got any non-destructive ideas as to what to use?

 

If anybody has any thoughts/help/suggestions on any/all of the above then I’d be very grateful indeed.

[carastro]

I can only say - Ouch!!  Can't offer any advice at all, but I feel for you.  Wow that's a huge burn hole. 

Carole 

[pete_l]

It takes some pretty serious current to generate enough heat to melt your EQDirect - and by the sounds of it your 2 previous power cables.

I would suggest you're on the right lines to notice that this has only happened since doing the belt mod. When you do that work, you have to remove the motors. The first thing I'd do would be to undo the body of the HEQ5 and have a look at the wiring. Check to see if the wires to the Dec motor get snagged in any position of the mount, or have any places where the insulation has been nicked. My guess - and it is only a guess  - is that the 12 volt supply to the motor is shorting to something inside.

Oh, and put a fuse in the supply to the battery. Next time, it could be that which catches fire!

[Xiga]

1 hour ago, pete_l said:

It takes some pretty serious current to generate enough heat to melt your EQDirect - and by the sounds of it your 2 previous power cables.

I would suggest you're on the right lines to notice that this has only happened since doing the belt mod. When you do that work, you have to remove the motors. The first thing I'd do would be to undo the body of the HEQ5 and have a look at the wiring. Check to see if the wires to the Dec motor get snagged in any position of the mount, or have any places where the insulation has been nicked. My guess - and it is only a guess  - is that the 12 volt supply to the motor is shorting to something inside.

Oh, and put a fuse in the supply to the battery. Next time, it could be that which catches fire!

Hi Pete

When I install the new motherboard I will have to remove the motors again, so maybe I will notice something when I do that. Although I couldn't see anything obvious when I had a brief look inside recently. I have been wondering though where the best place is for the wires to go. It definitely isn't getting stuck or snagged anywhere, but when I take the motor out I will inspect it's wires very closely for any signs of burning or anywhere that the wire casing might have been compromised (hopefully that's not the case!). Because the last thing I will need is to get the mount back up and running again only for the same thing to happen again.

I really need this to work, as I cannot afford a new mount any time soon :-(

About the power supply, I have grown to hate the Lead Acid type (such as the regular Celestron Power Tank ones that are very popular - I have one myself sure!). I think these types of power supply are more intended for delivering a lot of power for a brief amount of time (e.g jump-starting a car) whereas we really need ones that provide a low but steady amount over a long period of time. Is the Celestron Lithium (LiFePO4) power supply safer in this respect? I would hope that it would have some sort of protection against catching fire but knowing nothing about these things who am I to say!

[Adam J]

I would guess that the motors have been binding, you may find out that the dec motor / controller had blown. If you are really really lucky that may be because its unsoldered itself but its probably going ot need a new main board.  Take care though as it sounds to me as though if the main board has gone its because excessive current has been drawn though it you need to check the resistance across the motors and make sure they are nice and free before you plug in a new MB or if the problem is still there you will just blow the new one too. A fuse to the mount supply is a great suggestion as it will prevent any repeats. 

If the USB that the EQ Direct Cable was attached to is still functional then I imagine that the current surge did not originate from the PC but from the mount itself. At a guess one of the power fets shorted due to excessive current draw from the motor and the current subsequently got re-directed to earth though the EQDirect Cable. It is possible that the EQ Direct cable itself shorted and damaged the control circuit.....but not sure why it would just randomly short like that and the fact that the hand controller still works at all goes against that theory.

Bottom line...try to work out what happend prior to plugging in the new board as it may be a secondary failure, you don't want a repeat performance. 

 

[Xiga]

32 minutes ago, Adam J said:

....you need to check the resistance across the motors and make sure they are nice and free before you plug in a new MB or if the problem is still there you will just blow the new one too. A fuse to the mount supply is a great suggestion as it will prevent any repeats. 

Thanks Adam.

So if one major candidate here is excessive resistance on the Dec motor, do you know by any chance what particular part of the mount (grub screw or whatever) could be the most likely culprit? I do know that i was able to rotate the Dec cog & pulley by hand and it didn't feel that much different to the RA one. When i opened it up for a brief look i did at the time think that perhaps it was down to the Dec motor sticking, and i tried adjusting various screws/grub screws on the mount to see if i could loosen it at all, and found that i was able to make it even tighter than it was before, so i reversed what i did to loosen it again, but couldn't loosen the grub screw any more as it was already as loose as it would go whilst maintaining just the slightest bit of tension to keep it in place. Hopefully that made sense! lol. But in any case, all of this was after what had already happened. I will definitely make sure the Dec motor can freely rotate before i plug in the new board.

ps - Is there an easy way an electronics-numpty like myself can easily and safely introduce a fuse between the power supply and mount? Ideally without the need for any soldering?

[Adam J]

10 minutes ago, Xiga said:

Thanks Adam.

So if one major candidate here is excessive resistance on the Dec motor, do you know by any chance what particular part of the mount (grub screw or whatever) could be the most likely culprit? I do know that i was able to rotate the Dec cog & pulley by hand and it didn't feel that much different to the RA one. When i opened it up for a brief look i did at the time think that perhaps it was down to the Dec motor sticking, and i tried adjusting various screws/grub screws on the mount to see if i could loosen it at all, and found that i was able to make it even tighter than it was before, so i reversed what i did to loosen it again, but couldn't loosen the grub screw any more as it was already as loose as it would go whilst maintaining just the slightest bit of tension to keep it in place. Hopefully that made sense! lol. But in any case, all of this was after what had already happened. I will definitely make sure the Dec motor can freely rotate before i plug in the new board.

ps - Is there an easy way an electronics-numpty like myself can easily and safely introduce a fuse between the power supply and mount? Ideally without the need for any soldering?

Cant help with that to be honest, it may be worth moving the scope through the full range of motion to make sure its not binding at a specific point in its movement, it could be related to the meshing of the worm gear. I would measure the resistance of the motor too and compare to to the Az motor resistance in case its a failure is internal to the motor. Finally I would also check that there is not a short in the hand controller connection point (assuming its not a part of the new MB) although that may have shown up when you connected the hand controller itself. 

[Xiga]

Okay, good news. I installed the new motherboard tonight and the mount appears to be behaving as normal, slewing away happily in both RA & Dec. YAY!!!! 

Can't put into words really just how relieved i was to see the thing moving again. I probably would have had to pack the game in for a year or two otherwise. Phew!

However, there is a BUT...

I was originally under the impression that the USB port on the laptop that i had plugged the old, now fried EQDIR cable into, was ok, but it appears that it's actually not after all. At the time I only tested it by plugging in a 64Gb USB3 Flash Drive, and it recognises it just fine and i can access the files that are on it. However, i can't connect to anything else, be it phone, camera, or whatever. I only realised this tonight after i had got the mount working again, when i then went to test the new EQDIR cable. The new one is better than the old one, in that it remembers which COM PORT it is connected to, so that it shouldn't matter which USB port you connect it to, it always connects to the same PORT, which is one less thing to have to worry about. Well, of course my laptop wouldn't recognise the cable when plugged into the offending port. I then tried my mobile phone (it charges it but it doesn't show up as a device) and likewise with my Nikon D5300, it doesn't show up either :-( 

I had a look in Device Manager, but there are no exclamation marks or anything resembling an error. I also re-installed my USB3 drivers and re-booted, but still no dice. Does anyone have any other bright ideas, or am i just resigned to having a dead USB3 port from now on (ok it can still charge, but that's not of much use to me). Luckily I still have another USB3 port and one USB2 port as well, so hopefully i'll still be ok if i just get a USB splitter cable. 

The 3 USB devices i use are: Nikon D5300, QHY5 Guide Camera (this is the old, really old one), and the EQDIR cable. 

Would i be better letting the Nikon have the sole remaining USB3 port (due to the large file sizes), and let the QHY5 and EQDIR cable share the USB2 port? Is there any chance the QHY5 could interfere with the guiding pulses?

[kendg]

Sounds like it's time for a powered USB3 hub. 

I've got one and it works just fine for transferring Canon raw files with BYEOS, wireless joystick, autoguider camera and eqmod cable.

[Xiga]

So I was having a look at various powered USB Hubs this morning, and generally feeling a bit miffed at the thought of yet more cables (but more so the need for yet another power cable) and then it hit me, my laptop (Lenovo X230) has an ExpressCard 54 slot!

So I have just ordered the card below. It should give me 2 more USB 3 slots to work with, and sure even if they are not full speed I won’t mind, just as long as they allow me to connect to devices. I don’t see any cooled cameras on my horizon any time soon (certainly not within a few years at least) so my USB power needs are not extreme by any means. And the best part of this is, no more additional usb or power cables, or having a hub sitting about in extreme cold or dew. Once it arrives I’ll post a quick update to confirm I can connect ok to my D5300 and QHY5 guide camera, in case it helps any others. So it only took a total of £160 but it looks like I might be back in the game now, lol.

 

https://www.amazon.co.uk/gp/product/B00PJW5Q26/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

 

ps – For anyone who is on the lookout for solely a new imaging rig (i.e not for processing) I highly recommend a Lenovo X230. They’re rugged (important!), have plenty of USB slots (and an ExpressCard slot!), have good battery life, and the best part is, because of the student and professional markets they are a dime a dozen and you can pick up a refurbished one for next to nothing. I got a refurbished one with a 180GB SSD for just £150, which means it would even be fast enough to do planetary too. Highly recommended!

[andyboy1970]

You could plug the Dec motor into the RA socket on the old motherboard to see if it works, at least you will know if the motor is the problem.

I recently had an issue on my EQ6 were the cable from the handset socket to the motherboard had a dodgy termination cause the power light to flash rapidly. It was an easy fix to resolder the pins.