Wondering if anyone has any insight on this? I have a 165 fish hawk with a 80 lb ulterra. So twice now, I had my batteries go dead on me after less than 4 hours of use on the river in current running between 6-8 power level. My batteries are northern 27ev. Shouldn’t I be able to get at least a full day out of them? Both batteries were fully charged to start the day. I just tested my on board charger and everything checks out on that.
Thanks
If you were running 6to8 for 4 hrs steady , on group 27 batteries, I wouldn’t expect much more . You could upsize to groupn31 batteries and get more runtime possibly
Quit trying to pull upstream at the high bridge! J/K
If your running 6-8 on power upstream with a 16.5 ft boat then your asking your trolling motor to do the work of a kicker motor. If you were fishing the mississippi within the past week or two the flow has been over 30,000 so pulling against the current will put quite a strain on your batteries.
Besides running at 60-80% power draw, check your wire connections and guage wire for delivery to the motor. Corroded connections and under sized wire will have a big impact
Besides running at 60-80% power draw, check your wire connections and guage wire for delivery to the motor. Corroded connections and under sized wire will have a big impact
I’m with Randy, the biggest ground and power wires,goes a long way.
Thanks guys! I did have my big motor running also, when trolling up current and just using the trolling motor to stear, so it wasn’t doing all the work. Does anyone think if I went with a better battery, like interstate or something I would get more run time? I’m new to this, I went from a 12v 55 last year to this, and was expecting more run time from this one.
Lol! You know it was a down current bite right?
One word. Oddessys.
Max amp draw for that motor is 56. At 100% usage, over 4 hours you would consume roughly 236 amps from your batteries. This would be halved since its a 24 volt system. You should have had plenty of juice yet. What is the reserve capacity and marine cranking amps of those batteries? Judging by your boat being a 16′ that ulterra is way bigger than what you should need. I speculate that the wiring in your boat is of light gauge because normally you wouldn’t have that high of a load on it. To get best performance you should have 6 gauge wire. I bet it’s 10.
How old are the batteries?
Or one battery is bad….
I had Northern 27’s with a 17′ boat and got just fine performance out of them with the right wiring… right up till a cell went bad in one of the batteries. Then it slowly was worse until I figured it out.
I went to basically the same batteries, in the next size up, run time is really good now. And they are always maintained with a very good charger.
Max amp draw for that motor is 56. At 100% usage, over 4 hours you would consume roughly 236 amps from your batteries. This would be halved since its a 24 volt system.
According to the MinnKota spec sheet, the max draw is 56 amps at 24 volts. If this was supposed to be halved, would not the spec sheet reflect this in their literature?
I meant the amp draw is spread across 2 batteries not one. 56 amp is peak draw, at peak for 4 hrs you would consume 236 amps. That would kill 1 battery but since it’s a 24 volt system it’s spread across both batteries so roughly 120 amps consumed in total per battery. Good condition those batteries should have had plenty of juice left. I suspect bad battery(s) or high heat being caused by inadequate wiring.
Best thing to do is put a volt meter on each battery and check the readings at full charge.
I meant the amp draw is spread across 2 batteries not one. 56 amp is peak draw, at peak for 4 hrs you would consume 236 amps. That would kill 1 battery but since it’s a 24 volt system it’s spread across both batteries so roughly 120 amps consumed in total per battery. Good condition those batteries should have had plenty of juice left. I suspect bad battery(s) or high heat being caused by inadequate wiring.
Best thing to do is put a volt meter on each battery and check the readings at full charge.
Captain,
Your math is still incorrect. This is a 24 volt draw so the amps have to be figured at 24 volts also.
An interstate group27 battery will provide 160 amps @ 12 volts = (1920 watts of power) . Two of these wired in series will provide 160 amps @ 24 volts= (3840 watts of power, twice as much as a single battery).
You are correct that at 100% power the amp draw is 56 amps @ 24 volts. Four hours at 100% = 224 amps @ 24 volts. The op states he is running @60/80% of full draw, 70% draw for four hours would = 156.8 amps @24 volts.
The batteries combined, provide a total of 160 amps @ 24 volts and the draw is 156.8 amps @24 volts.
That is almost 100% discharge of the batteries, not a recommended practice.
The batteries in your example provide a combined total of 320 amps if they are 160 each.
There is no way those batteries should have been dead in 4 hours if they were in good condition and under the load he referenced. I’m sorry but your math is wrong.
Battery reads
marine crank @ 80F: 940
Cold crank amps @ 0f: 625
reserve capacity: 160
I checked voltage on fully charged battery and it was 13.44 in both batteries.I was to thinking maybe a bad cell also. Rapid marine installed the motor on the boat, and I believe it was wired already from crestliner. I do think your right it may be 10ga wire, I will have to look. So changing to 6ga will make a big difference?
Thanks again everyone.
Batteries are brand new this year and installed at rapid marine, how would I know if I had a bad cell?
The batteries in your example provide a combined total of 320 amps if they are 160 each.
There is no way those batteries should have been dead in 4 hours if they were in good condition and under the load he referenced. I’m sorry but your math is wrong.
Captain,
Please carefully re-read what I wrote. One battery will have 160 amps @12 volts. Two batteries will have 320 amps @ 12 volts. Two batteries will have 160 amps @24 volts. You CAN NOT get 320 amps @24 volts by combining these two batteries. Amps times volts equal watts.
I bought a Solar BA9 electronic battery tester on Amazon. Long story short it was able to pick out the battery I thought was going bad out of my 36 volt setup. A battery can fully charge and show good voltage and still be bad. Very little capacity left. This tester gives you SOC: state of charge, SOH: state of health, m ohms resistance and CCA: cold cranking amps. It told be my cranking/electronics was going bad. It was only 14 mo. old and I returned it under Warr. The others were 4 years old. 2 of them were rated 50% health and the one I thought was bad was rated only 30%. Being a 36 volt system I had to replace them all. ouch. At least the tester said the new batteries were 100% health
I agree with you huntindave. You cant add up the amps. The amps stay the same but the voltage goes up. The total watts available is additive. But weather its 12v, 24v or 36v its the same amps. Higher the voltage the more efficient the use of the available amps becomes.
Huntin Dave is correct!!!
<div class=”d4p-bbt-quote-title”>CaptainMusky wrote:</div>
The batteries in your example provide a combined total of 320 amps if they are 160 each.
There is no way those batteries should have been dead in 4 hours if they were in good condition and under the load he referenced. I’m sorry but your math is wrong.Captain,
Please carefully re-read what I wrote. One battery will have 160 amps @12 volts. Two batteries will have 320 amps @ 12 volts. Two batteries will have 160 amps @24 volts. You CAN NOT get 320 amps @24 volts by combining these two batteries. Amps times volts equal watts.
My bad huntindave! You are indeed correct. I was mixing up series and parallel and it’s impact on amps. In this scenario amps are not doubled but voltage is.
Thanks everyone, I had my batteries tested and they don’t seem to be bad, but the guy at rapid marine said he was surprised they went dead so soon and gave me replacements today. So I’ll run it this weekend and see how they hold up. Btw, my wire is 8ga from my batteries to the motor.
8 gauge may be enough. See attached chart 24v amps vs gauge vs length. Let us know how it worked out.
aps-vs-gauge-24v.jpg
Still only got 4 hours out of it this weekend. Just upgraded from 27’s to 31’s so hopefully I get more run time this weekend.
I have 27’s on my 80lb xi5 and I get a lot more run time on them and I’ve been doing a lot of pulling upstream while the flow was up. Something is just not right with your scenario.
I check back after the weekend and let ya guys know. Also mine has auto stow and deploy, so that takes a little juice.
Since you are all on the topic, I’m wondering if 14 guage is the right wire for a 24 v motorguide xi5 80 lb, I’m not sure I’m understanding the chart gizmo posted.
Since you are all on the topic, I’m wondering if 14 guage is the right wire for a 24 v motorguide xi5 80 lb, I’m not sure I’m understanding the chart gizmo posted.
NO! to read the chart you need to know the max amps that your motor can draw AND the length of the wires between the batteries and the motor. First find your amp number in the far left column in the chart. From that number and on the same line as that number, move along to the right until you get to a number equal to or greater than the length of the wires. From the wire length number in the chart move back straight up and at the top of the column, you will find the wire size you need to use.
as an example lets assume your motor draws 50 amps and the wire length you need is 15 feet.
Going down the left hand column we find 50 amps at the bottom line. Moving to the right we find 13 feet, not enough. Next number is 21 feet, yes that is long enough. Moving straight up that column at the top we read the number 6 and we have our answer.
6 gauge wire will safely carry 50 amps over a distance of 21 feet. If we needed to reach 23 feet then we would need to increase our wire size to 4 gauge wire.
Have you thought about adding a MK2-DC charger to the boat.
Then you could just start the main motor after a few hours
and get above idle to recharge the batteries.
You would need to check the output of your alternator.
I spot lock constantly and when we are camping at Kab
without access to electricity for a week,
it becomes a non-issue.
I have an 80 LB 24V Terrova
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