Torquedo or Epropulsion electric outboards.

scobo

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Did you notice any sound from the motor Scobo?
I always think the Torquedo has an unpleasant whine compared with the ePropulsion
Some say that the vibrations from an electric put the fish down but I have trailed flies 6’ from the outboard traveling at quite a speed just to see, both brownies and sea trout have come to the flies it would seem unaffected
Aye, fairly noisy compared to other motors.
Certainly didn't seem to bother the fish though. The guy motored across a bay just as I was heading for it but when I got there, I had a take first cast then went on to take 3 fish and miss a a few more within an hour or so.
As Col said, it's a weird bulky looking thing but then part of it is the battery so you'd expect it to be bigger than an normal leccy motor.
The ePropulsion looks much more compact.
Be interesting to see how the 24v 100lb Bison compares certainly.
 

scobo

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Col, I'm wondering if you really would need 2 of those 50ah 24v batteries.
The eProulsion battery is 1276wh and the ultramax is 1200wh (24v x 50ah).
The eProulsion draws 1kw of power and the Bison 1.3kw so not a great deal of difference.
I see the 60ah ultramax is only another 50 quid too. That would be 1440wh.
 
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ed_t

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When i was a kid i dabbled with radio controlled cars, the tamiya kit jobs.

Standard speed control was basically a variable resistor that wasted power to heat the resistor and reduce voltage to motor. If the bison has resistance speed control it will use much more juice for low speed work.

The alternative was FET (field effect transistor) speed control that pulsed the voltage, no resistor and much better battery use. Losses give or take reduced to the power draw of the control circuit. Fets do get hot so loose power through heat, but trivial to a resistor.

Thats for permanent magnet dc motors.

The unpleasant noise from the new-fangled things is interesting: i've worked on various AC machines with variable speed drives, aka variable frequency etc.

These use power transistors to pulse dc voltage into standard 3-phase squirrel cage motors (no i don't know why they are called that) that have stator and rotor windings but no magnets. They are very efficient when reduced power is required.

One of the side effects of the vfd is the motor noise is no longer a low constant hum but you get different pitches of squeeling at different speeds and power output.

Outcome is you might not be comparing apples to apples with regards motor types or speed control so energy requirement for 1 system could be much lower than another.

I've also worked on hybrid propulsion systems for cargo ships. One flavour of modern propulsion is electric drive props, multiple generators and battery storage. Rules require a second distribution system and backup "take me home" generator. If main system goes bang you have reserve to limp home. I'd always suggest a second battery whatever system.
 

scobo

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I'd always suggest a second battery whatever system.
I would agree, particularly on larger waters.
I was thinking you could get away with a 60ah ultramax and maybe a 10ah as backup ??
 

scobo

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The 24 V batteries are 50 AH ones.

Col
Yeah, sorry I meant 50ah. 🤪
It's capacity is 1200wh though, much the same as the ePropulsion battery. And the Bison is only rated 300watts more than the ePropulsion.
So if you went with the 60ah, that would account for the slightly higher power draw and the running time should be around the same.
 

Cap'n Fishy

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Yeah, sorry I meant 50ah. 🤪
It's capacity is 1200wh though, much the same as the ePropulsion battery. And the Bison is only rated 300watts more than the ePropulsion.
So if you went with the 60ah, that would account for the slightly higher power draw and the running time should be around the same.

Aye, it's more the concept of having 2 batteries, rather than one. You could spend £1600 on an ePropulsion (or whatever a Torqeedo is) and have one battery, or spend £1100 on a 100 lb Bison and have 2 batteries... plus a motor that is height-adjustable... and a bit cheaper to repair...

I just never like being out on a big loch with only electric power and only one battery...

Col
 

scobo

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Aye, it's more the concept of having 2 batteries, rather than one. You could spend £1600 on an ePropulsion (or whatever a Torqeedo is) and have one battery, or spend £1100 on a 100 lb Bison and have 2 batteries... plus a motor that is height-adjustable... and a bit cheaper to repair...

I just never like being out on a big loch with only electric power and only one battery...

Col
Fair point Col. I was thinking a smaller battery as a backup but on a loch the size of Hope, a second 50ah would be more sensible.
I guess if you look at it that way, the eProulsion would be £1600 plus £800 for a spare battery.
 

Cap'n Fishy

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Fair point Col. I was thinking a smaller battery as a backup but on a loch the size of Hope, a second 50ah would be more sensible.
I guess if you look at it that way, the eProulsion would be £1600 plus £800 for a spare battery.

Yeh - that was partly why I was having a think about the 100 lb Bison option. Plus the design issues...
 

mhw

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Yeh - that was partly why I was having a think about the 100 lb Bison option. Plus the design issues...
Absolutely agree with the comfort factor of having a reserve battery on board
It was one of the main considerations when considering the eP, would I get a full day with one battery in all conditions
So far yes
The digital readout showing % used gives a good indication as to when its time to head for home but more experience will also be invaluable
One comment on height adjustment which is something the eP doesn’t have
I disengage the the tilt lever and hold the motor at an angle with the prop just sub surface, far from ideal I know but it does enable creeping into weedy corners etc
And the entire kit can easily be carried which is pretty important when fishing the likes of Loch Cam, Assynt. That banking between the car and the boat is a killer
Martin
 

Cap'n Fishy

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Absolutely agree with the comfort factor of having a reserve battery on board
It was one of the main considerations when considering the eP, would I get a full day with one battery in all conditions
So far yes
The digital readout showing % used gives a good indication as to when its time to head for home but more experience will also be invaluable
One comment on height adjustment which is something the eP doesn’t have
I disengage the the tilt lever and hold the motor at an angle with the prop just sub surface, far from ideal I know but it does enable creeping into weedy corners etc
And the entire kit can easily be carried which is pretty important when fishing the likes of Loch Cam, Assynt. That banking between the car and the boat is a killer
Martin

Yeh, cheers, Martin... it's all swings and roundabouts... decisions, decisions... :unsure:

Col
 

mhw

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Yeh, cheers, Martin... it's all swings and roundabouts... decisions, decisions... :unsure:

Col
Just an aside to my last post re Loch Cam
The dog got bitten by an Adder whilst sniffing about in the heather at lunchtime
He immediately became pretty unwell and was obviously going to need a vet leaving no alternative but to set off looking for one
Back at the mooring I had to carry the dog,2x110 batteries, Minn Kota plus all the gear up the banking as fast as I could
Which just about left me needing a doctor
Then set off at speed to Bonar Bridge where I hoped there would be a vet
There wasn’t the nearest being in Tain
Off again, by this time Snowy was in a really bad way, on arrival at the vets they said we should say our goodbyes and they would do the necessary
We couldn’t accept that and asked if there was anything at all that could be done
The only hope was to take him to their headquarters in Invergordon
Off again, he was put on a drip and we found a hotel
They phoned at 2100 to say that there was a positive response to the fluids and by 0900 next morning they said we could take him providing we took him immediately to his own vet in St Andrews
Eventually he made a full recovery
The vet in Invergordon was excellent
If ever there was a day that focused the mind on travelling light that was it
Martin
 

franticfisherman

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Wow, the price of those LiFePO4 batteries has come down a lot. Apart from the price, the other thing that put me off them was the relatively low maximum discharge rate but this seems to have been solved now. I think I would go for one of those if my LiPo arrangement (which was built with the help of Cap'n Fishy and scobo) ever catches fire/explodes etc. During last years lockdown I upgraded it with another 2 batteries and Ihave never run out of juice yet. And I can charge my phone as well!


IMG_0548.jpg
 

scobo

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Wow, the price of those LiFePO4 batteries has come down a lot. Apart from the price, the other thing that put me off them was the relatively low maximum discharge rate but this seems to have been solved now. I think I would go for one of those if my LiPo arrangement (which was built with the help of Cap'n Fishy and scobo) ever catches fire/explodes etc. During last years lockdown I upgraded it with another 2 batteries and Ihave never run out of juice yet. And I can charge my phone as well!


View attachment 38093

Hi Phil, nice setup there. 👍
I ditched the Lipos last year after one went bad in favour of a bank of 18650 cells but I'm kind of wishing I'd saved myself the time and hassle by just getting one of those ultramax batteries.
Not that much more expensive either.
Having said that, the 18650's are cheap and easy to replace should any bite the dust.
 
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franticfisherman

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Thanks Scott, of course I had to buy a decent battery charger as well, it wasn't cheap but I can now charge all 8 batteries from storage level to full in just 90 mins. I hadn't heard of these epropulsion motors before, after looking at some comparisons on Youtube etc. I think I would choose one over the Torqueedo. I also noticed they are in short supply. Why do they call the 3 different shaft lengths extra short, short and long! What's wrong with short, medium and long? It would make more sense!

frantic
 

franticfisherman

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Just to round off this thread, I may have spotted a potential problem with the LiFePO4 type of battery. According to Wikipedia, they have a constant voltage during discharge. This means that monitoring the voltage during use won't tell you how much capacity you have remaining. As the battery approaches the fully discharged state, the voltage drops suddenly.

The battery's internal circuitry will protect it from damage resulting from over-discharging but If that happens and it switches off, you won't be able to get back to your launch site. It could help to use a low voltage alarm which sounds just before the switch off so you get a chance to head for home.

You need to think carefully about buying a battery (or two). which has the capacity to sustain your day on the water without going flat when you least expect it! We all suffer from 'range anxiety' and it'll get worse when we have to buy electric cars!

frantic
 

scobo

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According to Wikipedia, they have a constant voltage during discharge.
I'm not sure where they're coming from there Phil. :unsure:
Our solar battery system is lifepo4 and the voltage definitely drops as the batteries discharge. You can see this with the monitoring software or by measuring it at the terminals.
That's a really odd statement on wikipedia !!??
 

Cap'n Fishy

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Aye, the ePropulsion motors definitely have a '% charge remaining' gauge on them, so you can manage your usage through the day.

But if I was going down the 24 V 100 lb Bison route, the whole point of going that way would be to get 2 lithium batteries, so I didn't have the 'range anxiety'.

Col
 

franticfisherman

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I think Wikipedia must mean that the discharge curve is a lot flatter than other types of battery, if you look at the tech spec of the Ultramax it only varies by about half a volt between full and when it 'drops off the cliff'.
If you are monitoring with a good voltmeter this is not a problem. My LiPo pack varies by about 1.5v as it goes from full to flat so it is easier to keep an eye on and estimate how much charge is left without referring to tables.
Gosh! Does this mean that we can't believe everthing we read on the Internet! Horrors - I think I'm having a meltdown!

frantic
 

scobo

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Our Pylontech batteries charge to 54v when full and drop to about 48.5v at 10%.
There's 15 cells rated 3.2v which go from 3.2v to 3.6v. Not a great difference. Maybe that's what the wiki is referring to ??
But a 24v ultramax will presumably consist of 8 x 3.2v cells so there will be a more noticeable variation in the total voltage.
 

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