Lofrans cayman 88

sailaboutvic

sailaboutvic

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i fitted a new 1000w lofrans windlass a month ago .
ever since , now and then the breaker would trip when lifting the anchor .
to day I found that the cable at the solenoid got so hot , that it melted part of the solenoid .
I used the same 100A breaker that was on my other windlass , the cables are big cables which was fitted when the boat was build very large cable , slightly bigger then battery cables
When testing the volts at the battery it read 12.8 , at the breaker 12.8 and at the solenoid which is right up by the windless 12.8
With the engine running they all read 13.4 V
As soon as I use the windlass at the breaker read 11.8 and at the solenoid half a volt less .
It seen there is a voltages drop ,
Can anyone say what I would expect as a drop , how best to test to find the drop.
In simply terms , not that great with electric .
Any other advise please
 
Each volts drop means a resistance to current flow. From Ohm's law the power developed by any resistance will be I x V.

I would to measure the voltage directly across the solenoid with the windlass under load.

The overall volts drop around the circuit will consist of: the windlass motor load itself, cable losses, any poor contacts.

Poor contacts may not show up without a high current flowing, so appear low resistance when checked with an ordinary ohmmeter.

So assuming your current is approaching your 100 amps then 100 x 0.5 = 50 watts. Remember how hot a 60 watt lightbulb gets, this heat is now developing across the quite small contacts of your solenoid.

The overall power of the windlass will reduce with the voltage across it, but if this means it is not developing enough torque then the motor will draw even more current to try to maintain its motion, and hence more current flow = heat (I x I x R).

Did you replace the solenoid when you fitted the new windlass ?

I would strip and clean all cable joints assuming you are using cable at least 50 mm2 if not heavier. It is also worthwhile using an IR thermometer to check temperature of the cable joints after a hefty hoist session as this might reveal a hot spot and hence high resistance connection.
 
superheat6k said:
Each volts drop means a resistance to current flow. From Ohm's law the power developed by any resistance will be I x V.

I would to measure the voltage directly across the solenoid with the windlass under load.

The overall volts drop around the circuit will consist of: the windlass motor load itself, cable losses, any poor contacts.

Poor contacts may not show up without a high current flowing, so appear low resistance when checked with an ordinary ohmmeter.

So assuming your current is approaching your 100 amps then 100 x 0.5 = 50 watts. Remember how hot a 60 watt lightbulb gets, this heat is now developing across the quite small contacts of your solenoid.

The overall power of the windlass will reduce with the voltage across it, but if this means it is not developing enough torque then the motor will draw even more current to try to maintain its motion, and hence more current flow = heat (I x I x R).

Did you replace the solenoid when you fitted the new windlass ?

I would strip and clean all cable joints assuming you are using cable at least 50 mm2 if not heavier. It is also worthwhile using an IR thermometer to check temperature of the cable joints after a hefty hoist session as this might reveal a hot spot and hence high resistance connection.
Click to expand...

hi
the solenoid is new , it came with the windlass .
the only hot spot i can find is on the + lead on the solenoid and the up lead on the solenoid , would that mean thats where the problem lies ?
would you not say that the voltages at all points of the cable , ie at the battery , breaker and solenoid while the windless is working should all be the same .
I have already cleaned all the connection
 
sailaboutvic said:
hi
the solenoid is new , it came with the windlass .
the only hot spot i can find is on the + lead on the solenoid and the up lead on the solenoid , would that mean thats where the problem lies ?
would you not say that the voltages at all points of the cable , ie at the battery , breaker and solenoid while the windless is working should all be the same .
I have already cleaned all the connection
Click to expand...

You will inevitably get a voltage drop along the long cable when it is carrying such a large current Vic, so it's difficult to say whether 1V or 2V is a reasonable drop. In my experience 1V - 2V is the kind of drop you might expect but clearly something is wrong if the solenoid is getting that hot with normal, non-continuous use.

I had a 1000W solenoid with my 1000W windlass but after 6 years that melted at the top where the terminals are and failed. I've replaced it with a higher capacity 1.5kW solenoid to give me a bit more headroom as I now have 100m chain and a heavier anchor. After 3 years the new solenoid still looks perfect so I'm happy I upgraded it but that doesn't answer your question. If all the high current connections are clean and tight I don't really see what else you can do except try and use the windlass in shorter bursts and keep an eye on the solenoid.

Richard
 
RichardS said:
You will inevitably get a voltage drop along the long cable when it is carrying such a large current Vic, so it's difficult to say whether 1V or 2V is a reasonable drop. In my experience 1V - 2V is the kind of drop you might expect but clearly something is wrong if the solenoid is getting that hot with normal, non-continuous use.

I had a 1000W solenoid with my 1000W windlass but after 6 years that melted at the top where the terminals are and failed. I've replaced it with a higher capacity 1.5kW solenoid to give me a bit more headroom as I now have 100m chain and a heavier anchor. After 3 years the new solenoid still looks perfect so I'm happy I upgraded it but that doesn't answer your question. If all the high current connections are clean and tight I don't really see what else you can do except try and use the windlass in shorter bursts and keep an eye on the solenoid.

Richard
Click to expand...

should the connection get hot at all ,
I striping the solenoid and found the contact inside are badly burned ,
I manage to get most of the pitting out of them .
started to wonder if I got a dodge motor .
any way of telling , seen to work ok .
before any advise is given about driving the boat forwards , 45 years of anchoring . i think we got the hang of it now :) .
 
RichardS said:
You will inevitably get a voltage drop along the long cable when it is carrying such a large current Vic, so it's difficult to say whether 1V or 2V is a reasonable drop. In my experience 1V - 2V is the kind of drop you might expect but clearly something is wrong if the solenoid is getting that hot with normal, non-continuous use.

I had a 1000W solenoid with my 1000W windlass but after 6 years that melted at the top where the terminals are and failed. I've replaced it with a higher capacity 1.5kW solenoid to give me a bit more headroom as I now have 100m chain and a heavier anchor. After 3 years the new solenoid still looks perfect so I'm happy I upgraded it but that doesn't answer your question. If all the high current connections are clean and tight I don't really see what else you can do except try and use the windlass in shorter bursts and keep an eye on the solenoid.

Richard
Click to expand...

should the connection get hot at all ,
I striping the solenoid and found the contact inside are badly burned ,
I manage to get most of the pitting out of them .
started to wonder if I got a dodge motor .
any way of telling , seen to work ok .
before any advise is given about driving the boat forwards , 45 years of anchoring . i think we got the hang of it now :) .
up date
i removed one of the battery and connected jump leads from the battery to the solenoid the jump leads got hot .
the jump leads are the kind of cheap leads so not heave duty ,
but even so , such a short distant would they get that hot for a short time of use.

also i did a drop test
both neg and pos lead show an .78 drop when windlass is running , so I guess that show there no bad connection
 
Last edited:
When I stripped my old melted solenoid the contacts were burned out completely although mine was 6 years old and in regular use (regular mis-use?) by charterers.

I think what happens is the contacts get blackened over time due to sparking (same as the points on old car distributors) and this leads to a degrading connection which generates more heat and sparking which leads to more degradation .... a vicious circle. Eventually the heat melts the solenoid body.

However, I don't see why this would generate excessive heat outside the body of the solenoid nor why it would happen to a relatively new solenoid which is being handled correctly. :confused:

Richard
 
Does the solenoid operate freely? Is it possible that contact is being made too slowly, thus causing excessive arcing and, therefore, heat? Just a thought.
 
Heat across a high resistance contact is a product if current flow squared x resistance. A dirty contact passing a high current will generate heat that will conduct into its surroundings e.g the body of a solenoid with dirty contact faces.
 
I answered this once - but must have deleted the answer :(

We installed a Maxwell windlass 18 months ago. We specified it was for 6mm, EN818 - 2 chain (its a typical short link chain, quite common and Maxwell have a gypsy to match) and we used 8kg alloy anchors. We upgraded the motor to 1000 watts as we wanted the potential grunt, just in case. Increasing motor size was not a big issue, they have the same fittings, the extra cost was not large - the motor is just a bit longer. The Maxwell replaced a 8mm Muir windlass which also had a 1,000 watt motor. We used all the old cabling and circuit breaker but used the solenoid supplied by Maxwell. The Maxwell service was outstanding, the windlass easy to install and importantly it is very easy to service.

We have noted that retrieval speed is very fast, much faster then the old Muir Atlantic, of 20 years ago.

I don't think the Maxwell windlass is 'extra' special and believe most new windlass are fast, or very fast.

I have to wonder if your old windlass used the same motor, i.e. the old and new motor are 1,000 watts and though the cabling was adequate for the old, slow, installation possibly the new motor actually draws more power and very simply your cabling is now too small.

You do not mention chain nor anchor size but if your chain is 10mm and you are lifting bigger anchors, at speed - then power draw will be quite large, compared to the power draw at half the speed. Your power draw will also be much larger than us as we are using pretty minimalist chain and anchors - yet you are using the same sized motor.

One of the reasons for using lightweight stronger chain (and alloy anchors) is the reduction in power draw and possible to use smaller wiring, less need for bigger or dedicated batteries and smaller/cheaper windlass - and maybe this all illustrates the point (or not :) )

Jonathan
 
Last edited:
Neeves said:
I answered this once - but must have deleted the answer :(

We installed a Maxwell windlass 18 months ago. We specified it was for 6mm, EN818 - 2 chain (its a typical short link chain, quite common and Maxwell have a gypsy to match) and we used 8kg alloy anchors. We upgraded the motor to 1000 watts as we wanted the potential grunt, just in case. Increasing motor size was not a big issue, they have the same fittings, the extra cost was not large - the motor is just a bit longer. The Maxwell replaced a 8mm Muir windlass which also had a 1,000 watt motor. We used all the old cabling and circuit breaker but used the solenoid supplied by Maxwell. The Maxwell service was outstanding, the windlass easy to install and importantly it is very easy to service.

We have noted that retrieval speed is very fast, much faster then the old Muir Atlantic, of 20 years ago.

I don't think the Maxwell windlass is 'extra' special and believe most new windlass are fast, or very fast.

I have to wonder if your old windlass used the same motor, i.e. the old and new motor are 1,000 watts and though the cabling was adequate for the old, slow, installation possibly the new motor actually draws more power and very simply your cabling is now too small.

You do not mention chain nor anchor size but if your chain is 10mm and you are lifting bigger anchors, at speed - then power draw will be quite large, compared to the power draw at half the speed. Your power draw will also be much larger than us as we are using pretty minimalist chain and anchors - yet you are using the same sized motor.

One of the reasons for using lightweight stronger chain (and alloy anchors) is the reduction in power draw and possible to use smaller wiring, less need for bigger or dedicated batteries and smaller/cheaper windlass - and maybe this all illustrates the point (or not :) )

Jonathan
Click to expand...

Hi Jonathan
The cable is 12mm thick so I guess the iner core has to be at less 10mm if not 11 mm ,
I can't imagin that cable isn't big enough to carry the current
I really started to think there.a problem with the motor .
Our anchor is 25 kg and the chain is 10mm ,
But that don't come into it as their breaker trip well before we get to lifting the anchor .
We have a friend with the same windless who also has 10mm chain but his anchor is 35kg and he never had a problem .
Within pulling 20 mts of chair the trip goes .
As I said in the other posting .
An battery was place just by the solenoid with jump leads and within 10 second the leads got hot .
Any other ideas guys would be great before I take it off .
 
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One thing you could do is cut out the solenoid completely - wire the motor direct. You can the determine if there is anything wrong with the motor and if its not the motor its the solenoid (though it might be the terminals at the solenoid). You can use the circuit breaker as the switch - so that you can 'play around'.

It maybe in a later post but in your opening post you do not say if this is the old or a new solenoid. If its a new one you could put the old one into the circuit (as well as wiring the motor direct).
 
Last edited:
Neeves said:
One thing you could do is cut out the solenoid completely - wire the motor direct. You can the determine if there is anything wrong with the motor and if its not the motor its the solenoid (though it might be the terminals at the solenoid). You can use the circuit breaker as the switch - so that you can 'play around'.

It maybe in a later post but in your opening post you do not say if this is the old or a new solenoid. If its a new one you could put the old one into the circuit (as well as wiring the motor direct).
Click to expand...
It's a new solenoid , that came with the windlass , I did try and use the old solenoid but for some reason it turned the windlass over very slowly , not sure why , in the end of the day it's just a switch and it worked very well with the old S&L windlass .
I have brought a new solenoid but I don't want to fit it and burn out another solenoid ,
As the problem have been happening since I first fitted the new windlass I do wonder if I got an Friday night windlass .
 
Have you checked the wiring for internal corrosion? Peel back a little of the insulation near the solenoid and check the wiring is nice and shiny. If its black it is corroded and likley to be high resistance. If the wiring is tinned it is unlikley to be corroded but if it is plain copper there may ne an issue
 
geem said:
Have you checked the wiring for internal corrosion? Peel back a little of the insulation near the solenoid and check the wiring is nice and shiny. If its black it is corroded and likley to be high resistance. If the wiring is tinned it is unlikley to be corroded but if it is plain copper there may ne an issue
Click to expand...
Hi Geem
See #8 I did a drop test and found both the Neg and the Pos to have an 0.75 which if I am right indicate that there no resistance .
 
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