Wire

[SG]

Rick:

This is Andina's response...

I'm not a member of that board so I've not seen the posting. You can "quote post" my reply if you wish.

Rick totally failed to understand the fact that there is a battery at the far end of the feed. You are not relying on current from the alternator or the starting/house battery to operate the winch. The "surge currents" to which he refers are coming from the battery right beside the winch, not through the charging cable. With 100 feet of #10 cable there is no way you are going to draw enough current to do any harm to a Combiner 50 (which can actually take 100 amps continuous and 250 amps surge) because the voltage difference between the two batteries will always be less than a couple of volts. The connection is only for re-charging the winch battery and it will provide excellent voltage and current due to the close proximity to the winch. The 20 or 30 amps that pass through the charging line during winching are insignificant.

However whenever you have any power cable run that long it needs to be protected by a fuse to guard against accidental short circuits and a 100amp fuse for the Combiner 50 is going to be a FRACTION of the cost of a 750 amp fuse for the 4/0 winch cable. A stalled winch is going to draw much more than the 160 amps from the alternator because the winch battery will be able to supply CCA which could be well over 500 amps with a cable that heavy. Without at least a 750 amp fuse you can get the "nuisance" trips. If you blow the fuse on the Combiner charging circuit it is not a "nuisance" - the winch will still operate.

Readers report that it works great and with an UNCONDITIONAL warranty we've not had a single one returned despite Rick's paranoia.

The comment about the weight of the battery forward is pertinent depending on boat size. If 40 pounds forward is significant for the size of boat then you should probably be using a manual winch anyhow or pulling it up by hand on a boat that small.

Finally, there is no harm to the winch when sailing out - we do that frequently. But all good winch installations should have a one way chain dog that locks the chain to a spring mounted snubber that you engage once you are anchored. This is what takes the strain with some loose chain between it and the winch so no anchor shocks are transmitted. A winch should never be used as the anchoring post for a boat on the hook. Once the anchor is broken loose you can start the winch and the chain will pass through the dog in the UP direction.

Regards,

Andina Marie Foster,
tech@yandina.com

[Rick]

If I am "totally" famaliar with the arguments of using a battery at the winch end of cables vs using cables (which I have been for DECADES) than I could not have "totally" missed that fact could I?

The fallacy in using small wires to "charge" a battery significantly away from the source is that cruisers, in general, desire to recharge their batteries in a short of a time as possible. To be sure, I recognize that Andina may not have received any warranties or complaints regarding the "advised" combiner/battery/windlass installation, most technically informed sources advise against it for the arguments already given. The fact is that ANY battery capable of delivering 1200 to 2000 Watts of power to a windlass without a significant sag in terminal voltage WILL charge accept sufficient current to warrant the use of 2/0 cables (or perhaps larger) so that if the "far" battery is to receive rated acceptance voltage at the beginning of an acceptance "step" so as to become "full" at the same time (or before) the house battery is full (where in a combiner installation the alternator voltage sense wires are terminated) a #10AWG wire will not suffice.

I submit that the inferior installation begets loss of battery life to the windass battery which almost NO ONE out "there" is capable of testing and documenting in order to establish any "blame" of shortness of life. Because I am famaliar with such battery problems and HAVE been able to test, measure, and prove such things one MIGHT give some credibility in this regard.

Yes, I admit that perhaps no one has suffered financially with the "inferior" installations yet stand by my arguments, in general.

[Rick]

There is a machinist in my marina who has replaced or repaired two well-known (and respected) brands of windlasses due to gear and bearing damage from sailing out the anchor with the stress applied to the windlass.

One must give credibiliy to the windlass manufacturers who virtually all recommend against either laying to an anchor or sailing or powering out an anchor when the load is directly born by the windlass due to potential gear or bearing failure.

[Alan Wheeler]

I must state one major concern with SG's post. Andina has suggested that the 100ft of 10awg cable is going to have enough voltage drop across it to not allow enough load on the 50Amp combiner to cause it to fail. YIKES!!! Are you telling me that Andina is using the cable to be a voltage dropping/current limiting device That is just plain dangerouse. Voltage drop in a cable results in heat. Enough voltage drop produces enough heat to eventually cause the cable to fail and possibly start a fire. Cable should ALWAYS be spec'd to be able to supply the rated current/voltage that that line could possibly "see". The circuit breaker is there to protect the cable and the appliance at the end. If either should fail, the breaker should then trip.
Rick is correct in all his points (although I am hardly in his league to be able to pass judgment on him), although I do see benifits in a seperate battery system if the boat is big enough to warrant such. I suggest it would be boats of 55ft and up. Anything smaller and a simple insallation where batteries are in back near engine or where ever, is much more practicle.

And to add, an anchor winch is NOT designed to take high loads on a long term basis. You don't un-neccesserily load a winchin either operation or at rest. The winch only, should not take the pull of the anchor when set. And you should always manouver the boat forward to take as much load off the winch as it is raised. You may not burn the motor out, but you will wreck the gears.

Oh and one wee tip. Empty the gearbox of it's oil. Replace with a wynns product called Viscotene. You can buy it bulk, but it is hard to track down, so buy the spray can and be prepared, it is expensive, but It is majic stuff. The winch even runs faster.

[GordMay]

SG:
Thanks for providing “Yandina’s” input. I respectfully submit that Andina Marie Foster read the entire thread, that she might appreciate the full content & context of the discussion.

Andina suggests that you size the Fuse “up to” the Cable ampacity (4/0 Cable Fused at 750A).

”... However whenever you have any power cable run that long it needs to be protected by a fuse to guard against accidental short circuits and a 100amp fuse for the Combiner 50 is going to be a FRACTION of the cost of a 750 amp fuse for the 4/0 winch cable. A stalled winch is going to draw much more than the 160 amps from the alternator because the winch battery will be able to supply CCA which could be well over 500 amps with a cable that heavy. Without at least a 750 amp fuse you can get the "nuisance" trips ...”

This is totally wrong.
1. You size the Fuse to the Load, in this case 150 Amps. This protects the equipment. Lewmar specifies 150 Amp as the maximum operating current (above which any “Trip” is NOT a “Nuisance”, but genuinely “protective”).

BTW: 4/0 Cable is rated 378 to 440 Amp (not 750 A), depending upon ambient conditions & insulation ratings; hence you cannot fuse it over 440 Amp under any circumstances.

2. Then you size the cable to the fuse, in this case #2 or #4 AWG. This ensures the cable is capable of carrying the fused load.

3. Then you increase the size of the cable, if required, to reduce Voltage Drop to an acceptable level. A 10% Vd is permitted for a (non-essential) Windlass Motor, requiring a minimum wire size of 3/0 (150A @ 12.7V, 100 Cct Ft). As Rick noted, motor speed is commensurate with applied voltage, hence less Voltage Drop provides increased performance. Additionally, there is always some Vd associated with wire terminations. Thus, I recommend calculating (Windlass Feeders) for about 6% Vd (or less), which requires 4/0 Cable, in this case.

As Rick noted, the Engine should be running (for a number of reasons) when operating the Windlass. This will improve the terminal voltage, to something over 14V (Rick specifies 14.4V). Given that, why don’t I calculate Cable Size based upon an acceptable Vd of 0.8 - 1.4 Volts (Rather than 0.72 - 0.76Vd, I use)? I don’t believe that Battery Operated equipment should rely upon the Engine for proper operation, desirable as that Eng./Alt. running may be. Bigger Cable is always better, but at some expedient point I compromise between quality & money (even other people’s).

Andina also suggests that #10AWG Cable is acceptable for a 20 - 30 A Charging Current at 100 Cct. Feet.

”... With 100 feet of #10 cable there is no way you are going to draw enough current — The connection is only for re-charging the winch battery and it will provide excellent voltage and current due to the close proximity to the winch. The 20 or 30 amps that pass through the charging line during winching are insignificant ...”

Although #10AWG Cable is normally (NEC) rated at 30 Amps (ABYC allows 50 - 60 A), a 100 Ft. Charging Circuit of 20Amp @ 12V would require at least a #4 AWG cable, allowing a 10% Voltage Drop, and #2 AWG at about 5% Vd. A 30 A charging current would require cables between #1AWG and 2/0.

If higher charging currents are anticipated (as is desirable), even larger Cables would be required between the Charge Source & Bow Mounted Battery.

As others have pointed out, the effects of Voltage Drop can be insidious, and even catastrophic. Given a fixed source voltage, the only answer is more copper, larger cables!

Perhaps, now we know why the OEM installed a 24 Volt Windlass (Half the Current & Cable Size of a 12V machine).

FWIW,
Gord

[irwinsailor]

I was starting to get worried! I started to think that changing from the 24 volt system that is in the bow to a 12 volt system using the 12 volt house bank was going to be a mistake. The idea of making this change came from the Lewmar rep at the Chicago Strictly sail boat show.

[GordMay]

I’ve been waiting, impatiently, for the Automotive industry to make significant progress on the 42V Powenet protocol. Unfortunately, the practicable & ubiquitous implementation of the 42 Volt system hasn’t progressed as originally scheduled.

Adoption of the 42 Volt (or 42/14V Hybrid) system will be the Marine Electricians’ (hence Cruisers’) greatest blessing ! Of course , I’ll have to recalculate my Ft/Amp table to reflect the improved performance.

[CaptainK]

I hate to sound ignorant Gord.

My electronics is rusty at best here!! But what would the difference be if the industry were to change from the present voltage up to 42V?

What are the benefits in that? I just had to ask that. Since you mentioned that!!

[GordMay]

Current is inversely proportional to Voltage - any increase in Voltage, reduces the Amperage required to perform the same work.

A 2000 Watt motor, like Irwin’s Windlass will draw 143 Amps at 14 Volt, and only 48 Amps at 42 Volt.
At 14 Volt (12V) he requires 4/0 Cables & 150A Fuse, whereas at 42 Volt he only requires #1AWG Cables & 50A Fuse.

Amps = Watts / Volts
Amps = 2000 W / 14 V = 142.9
Amps = 2000W / 42 V = 47.6A

HTH,
Gord May

[Andina Marie]

Some responses:-

1.

The fallacy in using small wires to "charge" a battery significantly away from the source is that cruisers, in general, desire to recharge their batteries in a short of a time as possible.

The winch battery use is very similar to that of a starter motor battery - heavy loads for a short time. Even taking the maximum 150 amps for 10 minutes - a pretty tough winch job - uses only 25 amp-hours. To recharge this at only 10 amps takes 2.5 hours. If you are a sail boat and don't use your engine then you won't be able to recharge through either size cable. However most engines run at least this long between anchorages.

2,

The fact is that ANY battery capable of delivering 1200 to 2000 Watts of power to a windlass without a significant sag in terminal voltage WILL charge accept sufficient current to warrant the use of 2/0 cables (or perhaps larger) so that if the "far" battery is to receive rated acceptance voltage at the beginning of an acceptance "step" so as to become "full" at the same time (or before) the house battery is full (where in a combiner installation the alternator voltage sense wires are terminated) a #10AWG wire will not suffice.

While there is a voltage drop over 100 feet of #10 gauge carrying 20 amps, the voltage drop is Ohms x Amps. As the battery reaches full charge, the current drops to zero so the voltage drop also goes to zero and the battery gets a full charge.

3.

I submit that the inferior installation begets loss of battery life to the windlass battery which almost NO ONE out "there" is capable of testing and documenting in order to establish any "blame" of shortness of life. Because I am familiar with such battery problems and HAVE been able to test, measure, and prove such things one MIGHT give some credibility in this regard.

As I pointed out above, the winch application is very similar to a starting battery application where a high current is drawn for a short time from a battery that is not on charge. If this is detrimental to a winch battery we have a much larger problem with shortness of life on all our starting batteries. In fact short heavy discharge life is better than floating life since it tends to dislodge sulfation.

4.

I must state one major concern with SG's post. Andina has suggested that the 100ft of 10awg cable is going to have enough voltage drop across it to not allow enough load on the 50Amp combiner to cause it to fail. YIKES!!! Are you telling me that Andina is using the cable to be a voltage dropping/current limiting device That is just plain dangerous.

Do the math, Alan. #10 cable is approximately 0.001 ohms per foot so the total resistance is 0.1 ohms. With 20 amps charging current that comes to 40 watts or 0.4 watts per foot spread out over the whole length. That doesn't even make it warm enough to feel. This is hardly a "plain dangerous" heating problem. In fact we use 4 feet of the 10 gauge wire on the combiners to provide sufficient resistance to protect the contacts at up to 100 amps, not 20. We now have over 26,000 combiners in the field on unlimited warranty and there has never been a single problem with overheated cables in 13 years.

5.

Thanks for providing “Yandina’s” input. I respectfully submit that Andina Marie Foster read the entire thread, that she might appreciate the full content & context of the discussion. Andina suggests that you size the Fuse “up to” the Cable ampacity (4/0 Cable Fused at 750A).

You are correct, Gord. I was responding to an email from SG and had not seen the thread or the bulletin board. I made a rough estimate on stalled rotor current and grabbed a number similar to what we see on a starter motor. It appears that assumption was wrong and the fuse size should be adjusted to the stalled rotor current of the winch you are using.

Regarding the need for a heavier cable due to to voltage drop, see the responses above. If you need the winch battery charged within a minute or two then you will need a heavier charging line but a couple of hours minimum between winch use is not unreasonable.

6. I've read elsewhere that the 42 volt automotive idea has not only stagnated but has been abandoned.

7. If you want to install a 24 volt winch and not waste the second 12 volt battery just on the dedicated winch application take a look at our Trollbridge. It automatically charges the 24 volt battery from your 12 volt alternator and keeps the second battery in parallel with the house/starting battery. Only when you turn the winch on does it automatically put the batteries in series to give you 24 volts. The first model is limited to 80 amp winches or trolling motors, a 200 amp model will be available in about 6 months.

Regards,

Andina Marie Foster,
tech@yandina.com

[GordMay]

I’m very pleased to welcome Andina Marie, of Yandina Ltd (Marine Electronics) http://www.yandina.com/ , to our forum. I hope you will continue to actively participate, lending your considerable knowledge and experience to our (already considerable) wisdom bank.

Dialectic discussions, like these, enhance everyone’s understanding of the complex inter-relationships involved in designing and installing technical gear. We all benefit from differing, informed, viewpoints. Thank you for sharing yours.

Best regards,
Gord May

[Talbot]

I also wish to welcome your participation.

For other Forum members there are some very good articles on electrics of various type on the Yandina web site, including a very good explanation of the method to install a battery up forward for the thruster/windlass, and how to wire it into the rest of the system safely.

[Rick]

Andina has touched on an engineering truth in that wires may be operated within their "jacket rating" temperature that seems to violate the continuous current ratings. These ratings are referred to as "eye-squared-tee" (current squared times time) curves which all fuses and breakers have in order to make proper application.

For example, ordinary house breakers are rated for their current-temperature time values for a minimum specified length and sized wire on the load side (could be 10 inches, for example of #10 AWG wire).

In the case of Andina's recommended use of #10 wires in a circuit which is capable of delivering more than the continuous rating of #10 wire a breaker or fuse must be specified which will guarantee operation under all conditions which might exceed a 30A (at specified jacket temperature for that wire). I wonder if such combinations of breaker/fuse and wire jacket ratings are given for their installations. Most individuals do not have the technical knowledge to make intelligent choices for breakers and fuses in such extenuating applications.

Andina, it is obvious that you are not a battery expert. Start-only start batteries are designed to have a minimum internal resistance in order to deliver maximum current for a minimum sized battery. Statistically most starts in 12V automotive systems are less than 3/4 of an Amp-hour. Start Batteries are not, in general (flooded construction) designed to operate beyond 3% depth-of-discharge. Beyond that percentage cycling is referred to as "shallow-cycling". Beyond about 7% depth-of-discharge a battery is being deep-discharged. Shallow cycle start batteries do not have as good an internal resistance as non-shallow cycle ones yet are a compromise whose design was instigated when automobiles were designed to leave the headlights on for a timed-out period after the ignition is shut off. For awhile the new automobile dealorships supporting the new light time-out designs were PLAGUED with battery warranty problems (translation: cost to them) due to the shallow cycling rapidly degrading the start batteries not designed for such added stress on the very thin plates.

Batteries dedicated to only operate a windlass need to have shallow-cycle or deep-cycle ratings for best life and performance. Keep in mind that merely specifing a deep-discharge battery is not necessarily good due to the attendant increase in internal resistance, size for size. Windlass batteries, therefore, are NOT like start battery applications.

AGM and gel-cell batteries may be a very good solution for this application if they are good quality due to their capability of having both deep-discharge as well as low internal resistance as long as the charging system is designed for such batteries.

In addition, it is a myth that it is good to heavily discharge any lead-acid battery in order to remove sulphation. This myth began a long time ago when people only had lousy taper chargers which would only output significant current with the low terminal voltage of a discharged battery and not at float (there WAS no float merely a lousy line/load regulation of a taper charger). Taper chargers are neither constant voltage nor constant current chargers. So by heavily discharging a battery and rapidly recharging one the internal temperature caused by the charge/discharge current facilitated SOME removal of sulphate.

The proper manner to remove any accumulted sulphate is to apply an equalization charge regimen consisting of a constant current (3-7% of the so-called Amp-hour rating) until 2.7 gto 2.8 Volts per cell is reached. Almost no one "out there" has such a charger in the consumer world. Those purported to have an equilization capability are actually constant voltage applications which begin to do the job correctly yet fall far short of the proper manner of removing sulphation.

Sorry for the diatribe yet I have always had a difficult time "biting my tongue" when so many prevalent technical myths are promulgated by sources such as yours. No personal offense intended.
Regards,
Rick

[Alan Wheeler]

A very warm welcome to you Andina. I am glad you are here, as it is easy to mis-understand wording in posts and in hind site, mine was not well worded. Let me re-phrase my comment.
I had meant to say....
The circuit breaker is there to protect the load at the end of the cable. The cable has to be able to handle a short circuit of that load, without the cable failing or heating to a dangerouse level. Any resisitance in the cable is going to mean a certain amount of heat disapated along it in the event of a high load/dead short at the equipment the cable is supplying. Any current loss in the cable, equals less current at the breaker, equaling the difference in trip time and if indeed it will trip at all.
I was also infering that cable resistance should not be used to "regulated" voltage/currents. It's not the cables job. The cables job is to supply the V/I with as little loss as possible.

[Andina Marie]

Thanks for the battery selection info Rick. I have to admit my direct battery experience is getting old.

I have experienced premature death of battery banks on short cycling. It is purely based on empirical observations. See the article with an economical solution at Protect your battery banks from "short cycle" damage.