Alex_Blackwood
Well-Known Member
Yes you can. If you know what you are talking about!
Windlass Circuit Breakers
- Thread starter WindyWindyWindy
- Start date
WindyWindyWindy
Well-Known Member
For that you would need the information on what Lofrans consider to be suitable.
Do you have that?
Daverw
Well-Known Member
I’m a bit confused, are you trying to protect the supply cable or overload protection of the motor
PaulRainbow
Well-Known Member
In this case Dave, he has to do both, hence the need for a thermal breaker.
Graham376
Well-Known Member
I very much doubt it. In my opinion, you're looking for problems where none exist.
WindyWindyWindy
Well-Known Member
Well we've not covered that yet, what difference would that make?
PaulRainbow
Well-Known Member
For one thing, it is what Lofrans specify, hence my link to an appropriate 100a thermal circuit breaker, which fulfil your needs of it looking tidy (compared to the Lofrans model).
Generalising, fuses and circuit breakers are mostly fitted to protect the wiring, when there is an electric motor at the end of the cable that needs protecting too. If you fused for the motor load and you snagged your anchor, or overloaded the windlass in any way, the fuse would blow. If you increased the fuse rating you'll damage the motor if you overload it for too long. The thermal breaker allows you to slightly overload the motor, without harming it, but if you overload it too much the breaker will trip. Once it cools down you can reset it.
The BlueSea breaker is suitable and should be available Worldwide. If you search for the same breaker using "Bussman", "Cooper Bussman" or "Eaton" you can find the same breaker.
TSB240
Well-Known Member
Sigh.....
Paul has been pretty useful to you but you only demonstrate a low level of electrical understanding from your response to his answers.
Put simply a thermal overload will protect your cable and motor. The overload recommended by Lofrans and probably supplied to them by Bussman is a thermal overload! ( usually a bi metallic contact that heats up when too much current is drawn.)
A 100 amp thermal overload of this type may provide up to 2 or 3 times this capacity for up to 50 or 60 seconds. I am sure if you go on the blue sea web site you can establish this exactly.
I notice your chosen motor is actually rated at 135 amps! A motor demands significant inrush current to operate and sufficient to easily trip a magnetic breaker( think of a solenoid in reverse)or blow a 100 amp fuse.
So basically a thermal overload is required for this motor as it both protects the motor windings and the supplying cables in normal use and this is why a compromise of a 100 amps is chosen.
Many are unaware that once having tripped a thermal breaker may trip more frequently as they age or derate. This is usually a function of their price.
Paul has been pretty useful to you but you only demonstrate a low level of electrical understanding from your response to his answers.
Put simply a thermal overload will protect your cable and motor. The overload recommended by Lofrans and probably supplied to them by Bussman is a thermal overload! ( usually a bi metallic contact that heats up when too much current is drawn.)
A 100 amp thermal overload of this type may provide up to 2 or 3 times this capacity for up to 50 or 60 seconds. I am sure if you go on the blue sea web site you can establish this exactly.
I notice your chosen motor is actually rated at 135 amps! A motor demands significant inrush current to operate and sufficient to easily trip a magnetic breaker( think of a solenoid in reverse)or blow a 100 amp fuse.
So basically a thermal overload is required for this motor as it both protects the motor windings and the supplying cables in normal use and this is why a compromise of a 100 amps is chosen.
Many are unaware that once having tripped a thermal breaker may trip more frequently as they age or derate. This is usually a function of their price.
WindyWindyWindy
Well-Known Member
I do apologise for my ignorance and yes you've all been very helpful if a touch hostile.
But the confusion continues:-
Circuit Breakers for Windlasses - Accessories
And the difference between thermal and magneto-hydraulic breakers in this application still hasn't really been explained.
But the confusion continues:-
Circuit Breakers for Windlasses - Accessories
And the difference between thermal and magneto-hydraulic breakers in this application still hasn't really been explained.
Graham376
Well-Known Member
PaulRainbow
Well-Known Member
Good heavens !
The correct breaker for the windlass you referred to is the Lofrans 636089 , as specified here: SX2 - Vertical Windlass
That is a thermal breaker, as detailed here: https://www.lofrans.com/product/77-circuit-breakers/6411-thermal-circuit-breaker-surface-mounted
It has been explained, see posts #47 and #48
It requires no further explanation, because your windlass requires a thermal breaker. Just like the one i linked to, explained why you need it and told you the other names you can find it by searching the internet.
"A touch hostile" ?
That's not hostile, it's frustration at keep telling you the same thing and you not listening, so i'm done here.
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ean_p
Well-Known Member
Paul have you misplaced 'hydraulic' rather than 'Thermal' on line 3 as the quoted CB is a thermal modal I think......
PaulRainbow
Well-Known Member
WindyWindyWindy
Well-Known Member
That's fine, I was done a while back,as I explained. Then everyone started piling in.
But,the article you link to doesn't say why a thermal breaker is needed in this application. It actually suggests that they're just cheaper and more easily waterproofed.
To be clear I never claimed any knowledge. Just that the Lofrans breakers seemed expensive and asking what people's installations looked like. Only tranona actually did that. But I am grateful for the information supplied. The hostility is utterly baffling to me. I understand the frustration with dealing with idiots, like myself, but there's a lot of vague claims with limited facts here.
noelex
Well-Known Member
Magnetic /thermal breakers are superior to pure thermal breakers.
Basically the magnetic component responds to very high amperage currents. Thus rapidly protecting the wires and components from very high currents such as those that result from a short circuit. The thermal component provides protection from longer term mild overloads that might overheat components. Magnetic/ thermal breakers combine both protection mechanisms.
The only reason to use purely thermal breaker is cost. By eliminating the magnetic component the cost of the breaker is considerably reduced.
Many windlass manufacturers supply the superior Magnetic /thermal breakers as standard with their windlasses..
Absolutely Everything You Need to Know About a Thermal Magnetic Circui
Basically the magnetic component responds to very high amperage currents. Thus rapidly protecting the wires and components from very high currents such as those that result from a short circuit. The thermal component provides protection from longer term mild overloads that might overheat components. Magnetic/ thermal breakers combine both protection mechanisms.
The only reason to use purely thermal breaker is cost. By eliminating the magnetic component the cost of the breaker is considerably reduced.
Many windlass manufacturers supply the superior Magnetic /thermal breakers as standard with their windlasses..
Absolutely Everything You Need to Know About a Thermal Magnetic Circui
Alex_Blackwood
Well-Known Member
Yes a 100 amp circuit breaker! Thermal!
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Graham376
Well-Known Member
Agreed, it's spelt out on Lofran's site - Lofrans' anchor windlass circuit breakers What's not to understand?
WindyWindyWindy
Well-Known Member
Well, that they have two types of breaker, one of which has "a specific intervention curve has been studied in cooperation with E-T-A Germany".
Lofrans describe both types as "Circuit breakers for windlasses", but only one as a thermal type the other as magnetic.
So do other manufacturers breakers meet that specific curve?
How can you tell?
noelex
Well-Known Member
Most marine circuit protection is designed to protect the wiring. This is relatively easy. The appropriate protection is well documented.
Windlass circuit protection is slightly different. The circuit protection needs to protect the wiring, but also forms part of the protective mechanism to prevent the windlass motor overheating.
The windlass current or wattage rating is a very nominal figure. My own windlass is rated at 2kw but it will draw close to 10kw at full load.
The good news is that the exact matching of circuit protection to the windlass is not critical. Indeed, many windlass manufacturers produce only a small range of circuit breakers and use the same breaker for several models despite their different power ratings. Nevertheless, you should choose a breaker with the same or at least close to the same as the manufacturer’s recommend rating, and try to match the trip curve (or at least something close).
Finally and perhaps most importantly, choose something with a high interrupt rating. At full load many otherwise suitable breakers will be unable to interrupt the connection.
TSB240
Well-Known Member
From my memory the common trip characteristic of a thermal circuit breaker or as I am more used to calling them a motor overload protection device is that it will provide up to 200% of its rated capacity for up to 10 or 11 seconds.
In contrast a D Curve MagneticCB will trip within 1 to 1.1 secs of use at 100percent of its current capacity. It is about as much use as a slow blow glass fuse!
I am sure if you look on the blue sea web site you can acertain the veracity of my memory!
Good luck to you in your purchase
I'm out of here.
The phrase *You can lead a horse to water........................." comes to mind.?
In contrast a D Curve MagneticCB will trip within 1 to 1.1 secs of use at 100percent of its current capacity. It is about as much use as a slow blow glass fuse!
I am sure if you look on the blue sea web site you can acertain the veracity of my memory!
Good luck to you in your purchase
I'm out of here.
The phrase *You can lead a horse to water........................." comes to mind.?
