Using windlass resets the electronics

[thunderhoof]

Another approach is to add a relatively small lithium (to keep the same type) battery, say 10 AH, across the supply line near the electronics. This acts as a very large capacitor and should reduce voltage fluctuations to the equipment. It would charge in parallel with the main windlass battery. Additionally, a 0.5 uF, 50 V paper or plastic capacitor across the small battery terminals will reduce radio frequency noise from the motor affecting the electronics.

[LifePart2]

Thanks for all the ideas.

The Lithium cells are now two years old and in good shape.

I thought of running the windlass off the starter batteries. Maybe I will do that.

I also thought of putting a capacitor across the instruments, but was not sure that that would do the job. Would need to have a high capacity diode too, which also causes a half volt drop, so not sure of the practicality of that. Also I figured the large battery is essentially a huge capacitor, so why is that not doing the job? What about putting a coil in series instead of a capacitor in parallel? Would that work, and how big?

Will check the wiring again to make sure the windlass is indeed going straight to the battery.

Not sure when the problem started. Just in the last year or two. Perhaps since I put in the new batteries. They are Winston cells with no BMS as such, just my own careful automated monitory system.

I try to remember to switch on and off the instruments after and before running the windlass, but often forget.

Noel

[Tupaia]

Originally Posted by lmxr

- What lithium batteries and BMS do you have?
- What peak discharge current is the battery system rated for?

I would ask the same questions.
A lot of times batteries with internal BMS are insufficiently sized to rapidly deliver high amps. Lithiums designed for solar, for example, are expecting high loads via inverters that step the current up slowly (in electrical terms).
You can equate this to CCA (cold cranking amps) rating used for Lead Acid batteries.



There is a lot to be said for hybrid battery banks 1/3 LA and 2/3 lithium.

[lmxr]

Originally Posted by LifePart2

Thanks for all the ideas.

The Lithium cells are now two years old and in good shape.

May I ask how you come to the conclusion that they indeed are in good shape?

It is not uncommon to see lithium cells reaching end of life (EOL) after just two years due to an increase in internal resistance. The decrease in usable capacity may be minimal but due to the higher resistance the battery starts having difficulties to deliver high currents. This shows up as voltage drops when high currents are demanded, exactly mentioned symptoms...

I thought of running the windlass off the starter batteries. Maybe I will do that.

Works well, yet more or less implies that the engine should be running whenever the windlass is operated.

I also thought of putting a capacitor across the instruments, but was not sure that that would do the job. Would need to have a high capacity diode too, which also causes a half volt drop, so not sure of the practicality of that. Also I figured the large battery is essentially a huge capacitor, so why is that not doing the job? What about putting a coil in series instead of a capacitor in parallel? Would that work, and how big?

A battery indeed more or less acts a huge capacitor, albeit one with a relatively high resistance, and should smooth things out, which makes the voltage drops quite suspect.

A normal diode will indeed cause a non-negligible voltage drop. A FET like those used in charging distributors, for example a Victron ArgoFET, might improve things. A coil in series will cause the current to be continuous and will create voltage surges and dips whenever the current through it changes, so a coil might not deliver the desired result.

In the end these are not really solutions I'm afraid, they are more tricks that mask symptoms that shouldn't be occurring in the first place.

Will check the wiring again to make sure the windlass is indeed going straight to the battery.

Good idea. The problem popping up slowly might indicate a buildup of corrosion. I would try applying a sizeable load (10 A or so) through the same connections as the windlass and then measure the voltage drop, which ought to be in the mV range.

Not sure when the problem started. Just in the last year or two. Perhaps since I put in the new batteries. They are Winston cells with no BMS as such, just my own careful automated monitory system.

Well then the BMS for sure can't be causing any issues .

Suggestion for a test: swap the lithium battery for a fully charged lead-acid starter battery. Run the instruments and operate the windlass. Does this solve the issue?

[Emouchet]

This happened to me.
It took me a full sailing season and unnecessary $$ expenses until I found the culprit.

Check your windlass circuitry. There must be some corrosion somewhere that make a huge voltage drop.
I had exactly the same symptoms: windlass was weak and when under usage, it shutdown every other electric devices on the boat (electronic, fridge, light...)

I had corrosion on the main breaker. Once I found that, it took me 1 hour to disassemble it and clean it. problem was immediately solved. The main braker was warmed and was making a little buz.

Before checking on the main breaker:
- I changed the batteries in the bank (most people told me batteries where dead),
- Replaced the windlass solenoids,
- Wire directly the windlass engine on the batteries for a test (was perfectly working then),
- Replaced the wires from the main breaker up to the windlass anchor locker,
- Spent hours thinking on this, wreaking my time on the water,

All this for basic corrosion on the main switch... Good luck.

[LifePart2]

Originally Posted by Emouchet

This happened to me.
It took me a full sailing season and unnecessary $$ expenses until I found the culprit.

Check your windlass circuitry. There must be some corrosion somewhere that make a huge voltage drop.
I had exactly the same symptoms: windlass was weak and when under usage, it shutdown every other electric devices on the boat (electronic, fridge, light...)

I had corrosion on the main breaker. Once I found that, it took me 1 hour to disassemble it and clean it. problem was immediately solved. The main braker was warmed and was making a little buz.

Before checking on the main breaker:
- I changed the batteries in the bank (most people told me batteries where dead),
- Replaced the windlass solenoids,
- Wire directly the windlass engine on the batteries for a test (was perfectly working then),
- Replaced the wires from the main breaker up to the windlass anchor locker,
- Spent hours thinking on this, wreaking my time on the water,

All this for basic corrosion on the main switch... Good luck.

Thank you for this one. I have not had a chance to work on it yet, but I was beginning to suspect something like this, especially since I remember having to do something with the control solenoid a year or two ago.

I will go through all the connections and clean them. And lets see.

[Subtandard]

Originally Posted by LifePart2

When I operate the windlass, it resets (cuts and then restores power to) all my navigation instruments. Which is not good for them:
The raspberry pi may corrupt the SD card,
The Standard Horizon often does not reconnect the remote mic

Neither of these outcomes are ideal, and this occurs mostly when stopping the windlass, though it can also happen when starting it. When the chain is actually running, all is fine. I am presuming the inductive load coming on or off stream is spiking something, so how do I fix it?

We have a 300 AHr lithium battery pack. This connects directly to the windlass, and also powers the instruments. The Pi is powered through a DC voltage regulator that should provide a constant 5.25v, but clearly it cannot adapt fast enough.

I would have thought that the capacity of the lithium batteries would be big enough to smooth out the spikes, but clearly not.

Any suggestions?

Thanks

Likely the inductance of the windless motor is causing a voltage spike when you turn it off. I suggest connecting the windless to the starter battery and keep that separate from the house batteries that run the instruments when you are using the windless.

[Shaneesprit]

Motor inrush is widely considered to be 4 to 10 times the running current
I think you already know the answer.
It maybe possible to install a capacitor to keep the instruments supplied while the inrush takes effect.
Or another battery on the instrument side with a diode pack

[DeValency]

This is a known issue. Of course the engine is on when using the windlass but most alternators can’t compensate for the high consumption and basically are not designed to do that.

Your batteries may have the 300A rated capacity but most probably a BMS that restricts the discharge rate below the actual windlass power consumption.

The easiest thing is to add a small, isolated from the bank, LiFePo battery (say 30-50A) to support the instruments only. This will end the issue.
You can add more capacity to the bank to get enough momentary power but it is way more expensive and you may not have the space. If you do not really need a larger bank, I would just add the small instrument dedicated battery.

[Dieseldude]

It seems that the windlass inrush current is causing the voltage to sag, so this shuts down your electronics. A simple solution would be a small battery and some switches rated for the full load of the instruments. Before starting the windlass, connect the auxiliary battery to the instruments via the switch, and disconnect the main batteries from the instruments. Remember to restore the switches to normal position upon finishing windlass operation. It would be good to provide the auxiliary battery with its own charger, You might even keep your instruments powered by their own battery if you want to spend on a high capacity one, and keep the switching to run instruments from main batteries as a back up. The only limits on degree of redundancy are available space and money.

[Dieseldude]

Oh, another option might be a large capacitor across the instrument circuit feed. It will help to keep the voltage up during the inrush current. But what value of capacitor, I would not know. It would be a large one, not sure in microfarads, but it might be the size of a pop can. The electrical engineering to choose a capacitor would require the in rush current value and duration, capacitor discharge spec., and instrument load value. Large electrolytic capacitors are not cheap, could be as expensive as a battery. And the battery is more useful as a back up. If you have a source of used capacitors for free, would be worth trying. But at full price would be a costly experiment. Another problem is that when the capacitor recharges, it draws its own in rush.

[barryglewis]

We use Winston's for our 400amphr system,installed 2014. No automatic BMS, use a cell logger. Never had this problem. Also raise and lower 3 ton keel with electric-hydraulic system no problem like yours.

Apart from looking for a bad connection/solenoid/breaker, how do you check your cells are Balanced?

[beetle]

It's unclear if your instruments are dropping out due to low voltage (turning on the windlass) or a voltage spike (turning off the windlass).

Consider a DC-DC converter that will supply desired output voltage to your instruments. As long as the voltage isn't dropping too far then a DC-DC unit will keep things going, specify the converter to produce at least slightly more watts than your instruments draw.

If you're running NMEA-2000 instruments on as 12vDC system, use a DC 12vDC->15vDC converter and this will keep the NMEA network alive - even when large power draws such as autopilot cause reduced voltage in the NMEA-2000 network.

Something like this:
https://www.digikey.com/en/products/...-CMFD/13618295

- rob

[HankOnthewater]

Initially I was with post #11 and later with post #27. But alas no BMS to blame or poor lithium quality with having Winston.

I have the same anchor winch, and a similar sized lithium battery, but not together: winch is on my boat with AGMs, and lithium in my campervan.

In principle your size of battery should be sufficient, and with lithium there is not much voltage sag as with lead acid batteries. And that is something you can measure, on the battery that is.
Note that voltage drop in the windlass wiring and solenoids does NOT affect the supply to other needs, ie instruments, assuming they have a separate supply wires. This is voltage drop that affect the working of the windlass itself. Just check that where they combine that those connections are clean and tight.

If all these things check out, then I see only 2 culprits: cells are not balanced anymore, or one or more cells are damaged. You said you have this system without a BMS, then you have likely the skills to check these two possibilities out. Check the current capacity of your bank.

All the other measures in the previous posts might help your situation, but they may mask a problem.

Just a general question and I do not now the answer to that: can lithium batteries be damaged by an a voltage spike like stopping a large motor? Something similar to Lithium batteries be damaged by using a PWM solar controller?

[asinc]

Run the windlass from your starting battery, keep the engine running while using the windlass and run the electronics from your house bank. Done