electric trolling motor step up converter dc-dc

[_vn_]

Hello

Last year I purchased motorguide 36v Xi5-105 / 60" motor intended to use with my 25ft deck boat for occasional fishing, and I never got to install it due to complicated setup at the bow.
This year I came across a really good deal on an 16ft aluminum fishing boat and decided to use trolling motor for it.
However - carrying 3 heavy wet batteries adds extra 150lb weight to the boat which i'm not too exited about, and also the have to fit somewhere. Li-on packs are too expensive @ about 500 a pop with only 40ah vs 90 on wet batteries.
I found fairly inexpensive converter on ebay for around 80$ which claims to step up from 12 to 36v with max input 50a and output 30a (item number 253511417216), does price range sound right?
Has anyone used a dc-dc step up converter for such setup - 1 12v battery stepped up to 36v ? max amp draw of the motor is 41amp.

thanks !

 

[GA_Boater]

Your battery will be discharged in about 3 minutes - If you're lucky. Bite the bullet and buy batteries.

 

[_vn_]

i already have the wet batteries, its the space and weight i was trying to save in fishing boat, which was't really an issue in deck boat ...

 

[NYBo]

GA_Boater is exactly right. You won't get squat for run time. You might even burn out the converter as soon as you used the motor at full speed: it draws 41 amps vs the 30 amp rating of the converter.

 

[GA_Boater]

The other thing is trying to make something from nothing. It can make 36V, but it can't make current. Current is what makes the TM go around and what the battery stores.

What fishing boat do you have? We might be able to help you be creative.

 

[_vn_]

The other thing is trying to make something from nothing. It can make 36V, but it can't make current. Current is what makes the TM go around and what the battery stores.

What fishing boat do you have? We might be able to help you be creative.

Hi, its s blue fin or a starcraft, i replaced deck and will rebuild consoles from aluminum. I saw someone build a battery storage where consoles meet by creating a step up to a platform in front. Or another idea is to build a bench seat on the port side and put them in it but it will distribute weight unevenly.

 

[TyeeMan]

Is that a 105 lb thrust motor? If it is that is a lot of motor for a 16 ft tin boat. I have a 80 lb thrust 24 volt Minnkota Ulterra on my 20 foot lund IO and 90% of the time it is just fine.

36 volts, , you should get a good hole shot with that. :joyous:

 

[GA_Boater]

Hi, its s blue fin or a starcraft, i replaced deck and will rebuild consoles from aluminum. I saw someone build a battery storage where consoles meet by creating a step up to a platform in front. Or another idea is to build a bench seat on the port side and put them in it but it will distribute weight unevenly.

Looked through your past posts and didn't see what you have - What model? SuperSport or the BlueFin look-alike.

 

[H20Rat]

Way too much trolling motor for that boat. You can probably sell or trade someone for a smaller one and get some cash out of the deal.

Keep in mind watts = volts*amps. If your trolling motor draws 41 amps at 38.4 volts (3 12.8v batteries), it is 1574 watts. Divide that back down to 1 battery, and you are talking 123 amps of constant draw without even considering converter losses. That is almost 3 times the rated input of the converter (it would melt in a puddle), and even if it lasted more than 10 seconds, your battery would last a couple of minutes tops.

 

[_vn_]

Looked through your past posts and didn't see what you have - What model? SuperSport or the BlueFin look-alike.

its a blue fin 1984, not sure of a model, same hull as starcraft though

 

[_vn_]

Way too much trolling motor for that boat. You can probably sell or trade someone for a smaller one and get some cash out of the deal.

Keep in mind watts = volts*amps. If your trolling motor draws 41 amps at 38.4 volts (3 12.8v batteries), it is 1574 watts. Divide that back down to 1 battery, and you are talking 123 amps of constant draw without even considering converter losses. That is almost 3 times the rated input of the converter (it would melt in a puddle), and even if it lasted more than 10 seconds, your battery would last a couple of minutes tops.

got it
i have couple of ideas how to mount it on my deck boat, so i'll keep it even thought its an overkill for smaller boat.
maybe when li-on batteries will get more affordable i'll switch to that
i mainly want it to lock me on a spot when too much depth for anchor

 

[fishrdan]

That's a Chinese power supply, Ebay "DC Boost Converter 50A" and you can get it direct for $63...

That said, I wouldn't use it as it may put out dirty DC power, that may mess with the TM's PWM power supply and electronics. I have several 12/24V to 36V dc converters that I bought from Ebay (China) to run 36V LED fishing lights, they work to output 36V, but it's dirty power that messes with my fish finder....

I'd invest in new batteries, group 24 if you're looking save weight. I always get the biggest though.

 

[fishrdan]

Is that a 105 lb thrust motor? If it is that is a lot of motor for a 16 ft tin boat.

36 volts, , you should get a good hole shot with that. :joyous:

I have a 70# 24V MK on my 14' jon boat, no holeshot, but it try's to climb up onto the plane at max power.

 

[_vn_]

Is that a 105 lb thrust motor? If it is that is a lot of motor for a 16 ft tin boat. I have a 80 lb thrust 24 volt Minnkota Ulterra on my 20 foot lund IO and 90% of the time it is just fine.

36 volts, , you should get a good hole shot with that. :joyous:

hehe, like i said, was planning to use on deck boat, that was power recommendation
i'll try pulling wakeboarder and let u know later ! ))

 

[sam am I]

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