Running windlass with LFP

[noelex 77]

Originally Posted by Baronkrak

Curious. Any link to that information?

See here:

https://vetus.sharefile.com/share/vi...afae877921a4a4

It is a commercial windlass and Maxwell supply more technical information for these models than for their leisure range. It is a large heavy duty windlass but I imagine the characteristics and shape of the load v current draw will be similar for most models although the absolute values will be lower for smaller units.

[CaptainRivet]

If your BMS can handle that depends how ot does cutoff and if Mosfets are involved and how their specs are.
the BMS itself and cells won‘t have a problem handling that surge loads as peak has enough headroom BUT a lot of mosfets which are used as SSR in BMS to cut off are prone to fry when they get inrush current.
That’s identical to Victrons Battery protect which is stated in the manual not to be used for inverters and big motor loads as big inrush current will destroy it immediately.
I would just ask kilovault.

Major reason I got the Electrodacus BMS as it doesn’t carry any current only 2 shunts are physically in-line. So starter and windlass no problem as I have a cat with classic hybrid starter/house bank in one hull and starter in the other hull.
Handy and wanted to keep it that way.

[CaptainRivet]

Originally Posted by noelex 77

See here:

https://vetus.sharefile.com/share/vi...afae877921a4a4

It is a commercial windlass and Maxwell supply more technical information for these models than for their leisure range. It is a large heavy duty windlass but I imagine the characteristics and shape of the load v current draw will be similar for most models although the absolute values will be lower for smaller units.

Thats inline with classic calculation for a DC motor that startup is about 3x the cont current and stalling/inrush 5x cont current. No surprise here, so the peak load of BMS and cells should take that with a bit headroom into account as first check. 2nd mosfets inline as eg SSR, if yes what’s their spec and will they survive this inrush current? Only your drop in manufacturer know…

[noelex 77]

Originally Posted by CaptainRivet

Thats inline with classic calculation for a DC motor that startup is about 3x the cont current and stalling/inrush 5x cont current.

What surprised me, and would probably surprise most sailors, is the nominal wattage rating of the windlass is not at its rated maximum load.

So Maxwell rate my windlass in the specifications as 2kw and 4000lb, but at 4000lb the windlass will draw around 10kw.

The 2kw consumption will not occur at the rated maximum load but rather at something like 1/3 of the rated capacity and this is just considering the steady state current not the higher inrush current.

[Baronkrak]

Originally Posted by noelex 77

So Maxwell rate my windlass in the specifications as 2kw and 4000lb, but at 4000lb the windlass will draw around 10kw.

Not really. Maxwell specifications:

“Pull Capacity 1818 kg
stall 4000 lb”

A poor and misleading choice of words. Pull and Stall are distinct words.
Normally a windlass manufacturer should provide Safe Working Load and Breaking Load for their products. I regard 1818 kg as the BL of your windlass.
My own windlass BL (the manufacturer use Max Load other use Static Load for BL) is also rated at 1818 kg.

Classification Society 2023 use the followings terms:

Holding Loads
Inertia Loads:
Continuous Duty Pull: The windlass is to have sufficient power to exert a
continuous duty pull , Zcont1, over a period of 30 minutes
Overload Capability: period of at least two minutes short term pull: 1,5 times
the continuous duty pull
Hoisting Speed: 0,15 m/s.
Brake Capacity:

https://www.imorules.com/SSC_PT3_CH5_8.html

My own windlass specifications are:
24V, 60A, 1440VA protected by a mandatory 80A over-current circuit breaker.

Poor choice of words is often found in this forum. For example:

“Well people often have no glue"

“Meant resistive compared to conductive”

Obviously if poster have no glue, post like this should not stick.

“power factor or cos-pi: that is the factor the AC sinus wave curve is twisted and /or shifted (very simplified) and the inverter needs additional energy to map/re-allign it back to standard when this appliance is running. the power factor or cosi-pi simplified tells you how much it is twisted and how much energy the inverter has to waste to map/align it back to the 60hz sinus wave curve."

[noelex 77]

Originally Posted by Baronkrak

Not really. Maxwell specifications:

“Pull Capacity 1818 kg
stall 4000 lb”

A poor and misleading choice of words. Pull and Stall are distinct words.
Normally a windlass manufacturer should provide Safe Working Load and Breaking Load for their products. I regard 1818 kg as the BL of your windlass.

They are not my terms, but that of the windlass manufacturer. Maxwell post a graph referencing all the important parameters (see post #17).

Most windlass manufacturers use identical criteria (Lighthouse are the only exception I am aware of). They are distinct terms and seem quite clear. 1818kg or 4000lb is the maximum pull where the windlass cannot pull a greater load so the retrieval speed has reached zero. This seems a straightforward and it is how windlass manufacturers specify their product, so this windlass is a Maxwell 4000.

For example, if you buy a 2500 model from most other manufacturers the “2500” means the maximum pull when the retrieval speed has reached zero is 2500 lbs. Likewise a 1500 model will normally have a maximum pull of 1500lbs.

The SWL is different. Most windlass manufacturers specify the SWL of the windlass as 1/3 to 1/4 of the maximum pull. Maxwell use 1/3.

You seem to believe manufacturers should use SWL rather than the maximum load to name their models. I would have no objection to this change, (continuous load numbers would also be nice), but it is not the current practice and is unlikely to be commercially viable unless all manufacturers make this alteration.

The BL is not normally specified, but it seems unlikely that the BL would correspond to the maximum pull. Worm drive gear boxes are very tough and the windlass is protected by a circuit breaker. I would expect the maximum holding capacity to be higher than the maximum retrieval capacity.

Can you show why you think the windlass would break if it was subject to its maximum rated pull?

Originally Posted by Baronkrak

Poor choice of words is often found in this forum. For example:

“Well people often have no glue"

“Meant resistive compared to conductive”

Obviously if poster have no glue, post like this should not stick.

“power factor or cos-pi: that is the factor the AC sinus wave curve is twisted and /or shifted (very simplified) and the inverter needs additional energy to map/re-allign it back to standard when this appliance is running. the power factor or cosi-pi simplified tells you how much it is twisted and how much energy the inverter has to waste to map/align it back to the 60hz sinus wave curve."

?????

[Baronkrak]

Originally Posted by noelex 77

They are not my terms, but that of the windlass manufacturer.

Exactly.

Originally Posted by noelex 77

Maxwell post a graph referencing all the important parameters (see post #17).

Holding Loads is not represented.

Maxwell also post specifications (See https://vetus.sharefile.com/share/vi...afae877921a4a4
)

Originally Posted by noelex 77

Most windlass manufacturers use identical criteria. They are distinct terms and seem quite clear. 1818kg or 4000lb is the maximum pull .

Yes. it is the maximum pull (load) that the windlass can withstand or (BL). (See Holding Loads at https://www.imorules.com/SSC_PT3_CH5_8.html

Originally Posted by noelex 77

Most windlass manufacturers specify the SWL of the windlass as 1/3 to 1/4 of the maximum pull. Maxwell use 1/3.

Maxwell specification for Pull Capacity cont. run (1) (SWL) is 533 kg 1175 lb
and according to IMORules Continuous Duty Pull is limited to 30 minutes

Originally Posted by noelex 77

You seem to believe manufacturers should use SWL rather than the maximum load to name their models.

No BL is better.

Originally Posted by noelex 77

The BL is not normally specified, but it seems unlikely that the BL would correspond to the maximum pull.

The BL of your windlass is 4000 lb 1818 kg

Originally Posted by noelex 77

Worm drive gear boxes are very tough and the windlass is protected by a circuit breaker..

A circuit breaker will not protect your windlass from Holding Loads that exceeds the BL.

Originally Posted by noelex 77

I would expect the maximum holding capacity to be higher than the maximum retrieval capacity..

.
Yes you are correct. Maxwell 4000 maximum holding capacity 4000 lb 1818 kg, maximum retrieval capacity 1175 lb. 533 kg

Originally Posted by noelex 77

Can you show why you think the windlass would break if it was subject to its maximum rated pull?

Any equipment should not break if the equipment is subjected to its maximum rated pull.
I never subjected my windlass to more than the Overload Capability of the windlass 80A at 24V but this was sufficient to strip the threads from the coupling that join the windlass to the gearbox. By the way to minimize over loading, the windlass is equipped with an A meter, thermal sensors to monitor the motor, a fan to cool the motor and an extra grease nipple to improves the lubrication of the plain bearing. My record show that I purchased that windlass for aud $ 2134 in Feb 1998.

[rslifkin]

The 4000lb rating for Noelex's windlass is NOT a BL (breaking load). Because pulling against it with 4001 lbs is not going to break the windlass. The motor won't be able to pull the rode in with 4000+ lbs of tension, as there's not enough pulling power. But the windlass structure will hold more than that in a static situation.

Breaking load is a structural limitation. Max pull is power (and gearing) limited, not a structural limit.

On my Maxwell HRC10-8, for example, it's rated for a maximum pull of 1540 lbs. But they list "static hold" as 3300 lbs. In other words, you can put 3300 lbs of load on the windlass without it slipping backwards (clutch fully tightened and they don't specify if this is with the pawl engaged or not) or breaking. Even though that 3300 lbs is more than twice the force it takes for the motor to stall and not be able to pull anymore.

The HRC10-10, which is the same windlass (other than having a different gypsy supplied standard and a 1200w motor instead of 1000w) is rated with a max pull of 1870 lbs. Static hold is unchanged, which makes sense, as the gearbox and other mechanical components are the same, so the overall strength of the assembly hasn't changed. Just more power added to get a stronger pull.

[noelex 77]

Originally Posted by rslifkin

The 4000lb rating for Noelex's windlass is NOT a BL (breaking load). Because pulling against it with 4001 lbs is not going to break the windlass. The motor won't be able to pull the rode in with 4000+ lbs of tension, as there's not enough pulling power. But the windlass structure will hold more than that in a static situation.

Exactly

[Baronkrak]

Originally Posted by rslifkin

But the windlass structure will hold more than that in a static situation.

How much more?

[Baronkrak]

Originally Posted by rslifkin

But they list "static hold" as 3300 lbs.

Maxwell does not list “static hold” (See https://vetus.sharefile.com/share/vi...afae877921a4a4
)

Originally Posted by rslifkin

for the motor to stall

A bad idea to stall an electric motor.

Originally Posted by Jim Cate

I fully understand the need to relieve the windlass of anchoring loads... that's obvious, because there is basically no limit to them and they are repetitive, both in terms of torque applied to the gearbox and to bending loads on the shaft.
Jim

[noelex 77]

Originally Posted by Baronkrak

maximum retrieval capacity 1175 lb. 533 kg

If you look at the graph in post #16 you will see that the windlass will retrieve at loads greater than 533kg. The graph even shows the speed of retrieval.

For example with a 1000kg load the retrieval speed is just above 10 m/min. The motor cannot sustain 1000kg with a continuous duty cycle, but it can clearly retrieve chain with a load greater than 533kg.

Originally Posted by Baronkrak

The BL of your windlass is 4000 lb 1818 kg.

Originally Posted by Baronkrak

Maxwell does not list “static hold”

Maxwell do not list the static hold for the VWC 4000 windlass, but they do for their smaller VWC 3500 model. This has a static hold of 4840 lbs. So the static hold of the smaller windlass is well above the 4000 lbs that you claim will actually break the larger model.

I think you are misunderstanding the specifications.

[lateral]

If you are retrieving from cockpit, would an ammeter there be a useful addition?
Also, what back emf protection on shut off would be prudent to install?
I guess you can manually isolate sensitive electronics, or as previously suggested, bypass
the bms('s) as a cheap solution. A "T" class plus suitable ANL inline of course. Not ABYC compliant though.

[Baronkrak]

Originally Posted by noelex 77

If you look at the graph in post #16

The graph at post #16 indicate by the numeral 1 in a circle the speed of retrievals, the current and the voltage required for your Maxwell 4000 windlass. There is nothing else to extrapolate from that graph.

Originally Posted by noelex 77

Maxwell do not list the static hold for the VWC 4000 windlass,

Maxwell list “Pull Capacity 1818 kg
stall 4000 lb”

[noelex 77]

Originally Posted by Baronkrak

The graph at post #16 indicate by the numeral 1 in a circle the speed of retrievals, the current and the voltage required for your Maxwell 4000 windlass. There is nothing else to extrapolate from that graph.

I think you are not understanding the graph.

The speed of retrieval can be clearly seen.

Obviously if, for example, at a 1000kg (2200. Lbs) load the windlass is capable of retrieving chain at 10m/min its maximum retrieval capacity is not 533 kg (1175 Lbs) as you stated in post #22.

Originally Posted by Baronkrak

Maxwell list “Pull Capacity 1818 kg
stall 4000 lb”

Absolutely. The maximum pull capacity of the windlass is 1818 kg (4000 lb). Below this limit the windlass will retrieve chain, above this number the windlass can no longer turn.