Power tech motormover

[Redlac]

Hi all
Just purchased an elddis aurora van fitted with the above motor mover, I took my leisure battery from my old van and fitted it to this one, It was showing 12.2volts so had a problem with the motor mover cutting out. I recharged the battery and it was reading 12.8volts, Imoved the van about 3 yards and noticed the voltage dropped again to 12.2 volts, would this indicate the battery is faulty now. Also I have purchased a new 70ah leisure battery recommended for the van (not fitted yet) but have read I need a 110ah one. Can anyone shed any light on this for me.
Thank You

 

[birdman101]

If you have mover fitted 110 amp is the one as mover pull voltage down quite a bit.

 

[Beardy]

Did you mean Powertouch motor mover?
If so the manual for mine says:
'A 110-Ampere hour battery is recommended for optimum operation of the Powrtouch Evolution. Smaller batteries may be utilised but mover performance may be reduced.'
I can confirm that mine works OK with a 78ah car battery.

 

[Mr Plodd]

How quickly after coming off charge did the battery show 12.8v? To get an accurate reading it needs to be off charge for at LEAST 30 minutes before taking a reading
Was that voltage on the caravans built in meter, or a multi-meter. Caravan meters are notoriously inaccurate.
Try it with your brand new battery, it will be more than enough unless you have to use your mover for an inordinately long distance.
If it works fine then your old battery is clearly "an ex battery, its has ceased to be, it is no more, it's dead mate!"

 

[Sam Vimes]

I've used a 70Ah car battery on my 1200kg van to move it 30m up the driveway which is sloped at 25% in places. It had no problems.

 

[ProfJohnL]

Provided you always use the EHU when on site ( and at home before you leave) that should keep the battery (70 or 110Ah ) fully charged, and that should not cause any problems with the mover.

 

[Beachball]

We always use a 110Ah for our motor mover on our last caravan with no problems

 

[trevormonty]

Given you have 70AH battery I suggest use it and see how it performances. You won't break anything.

 

[Redlac]

Thanks Guys for the replies, I'm having to get an engineer out as the fault doesn't lye with the battery. It is over current on mosfet driver.

 

[ProfJohnL]

Thanks Guys for the replies, I'm having to get an engineer out as the fault doesn't lye with the battery. It is over current on mosfet driver.

I'm interested to know how you have established this diagnosis?

 

[Redlac]

I'm interested to know how you have established this diagnosis?

Hi
When I tried the mover with the new battery it done exactly the same, I got the manual out on it and noticed that when the mover tripped the ECB had two flashing lights, a red and green, the fault page said this was due to over current on mosfet driver, Engineer is attending on 24th April so I will post the outcome of the problem.
Thanks for your concern.

 

[Woodentop]

Is this a local engineer of a PowrTouch engineer? If it is the Powrtouch that is problematic you should contact them as they have techs all over the country that should be far better equipped than a local both in parts and between the ears!

 

[IanB1485]

Overcurrent implies the motor is at fault ( or output cables) not the driver , the electronics have detected the overcurrent , and shut down to protect the driver transistors.Based on my experience with motors I would say a winding on the armature is shorted to another winding. To check this the armature needs checking with a v low resistance meter , rotating it round and looking for a small change , The other way is to observe the armature, looking for burning/discolouration and at the same time cleaning up the commutator bar surface (and gaps). On the slight chance a MOSFET transistor has shorted , then disconnecting the motors and running the mover would show the same fault ( had this with a CNC punch machine), but again having dealt with lots of motor drivers and switch mode power supplies the driver transistors tend to explode as a damaged transistor is a lot faster than a fuse. The final cause would be a damaged gearbox , this is usually a failed bearing ( v rare) or shattered teeth and would create a grinding noise. I carry a spare motor assembly to check out the system along with a DC clamp on ammeter.

 

[Woodentop]

For the record, a power MOSFET is a positive temperature device, i.e. as it gets hotter so its resistance rises and the current limits. I have never seen an audio power MOSFET amplifier with failed outputs. Conventional transistors for instance do the exact opposite - as temp rises the resistance drops and the current rises into thermal runaway and blown transistors very quickly. Using power MOSFETS is a good move to improve reliability.

 

[Redlac]

Is this a local engineer of a PowrTouch engineer? If it is the Powrtouch that is problematic you should contact them as they have techs all over the country that should be far better equipped than a local both in parts and between the ears!

Hi
. It's a local engineer that I have used regularly. He's really good so will await the outcome. Hopefully another motor mover not required, Already had to cancel a holiday.

 

[Beachball]

Hi
. It's a local engineer that I have used regularly. He's really good so will await the outcome. Hopefully another motor mover not required, Already had to cancel a holiday.

Hope it a good outcome for you and it easy repairable ,🙏