HB-25 and trolling motor
w4fej
Posts: 264
Hi All:
I'm planning on using a 12VDC trolling motor for a remote control project and have some questions about how the trolling motor "works".
This motor uses what they are calling a "speed coil" and from what I can gather you feed these coils 12vdc to some how control the speed of the motor. Is anybody familiar with this method of controlling speed?? There are four wires going to the motor in addition to the heavy 12vdc power wires.
Can I simply tie 12vdc to one of the leads and use the HB-25 to control the speed?? What about reversing the motor with +12vdc tied in??
Any insight to how to manage this motor would be greatly appreciated..
Thanks for reading, Mike B - North Carolina
I'm planning on using a 12VDC trolling motor for a remote control project and have some questions about how the trolling motor "works".
This motor uses what they are calling a "speed coil" and from what I can gather you feed these coils 12vdc to some how control the speed of the motor. Is anybody familiar with this method of controlling speed?? There are four wires going to the motor in addition to the heavy 12vdc power wires.
Can I simply tie 12vdc to one of the leads and use the HB-25 to control the speed?? What about reversing the motor with +12vdc tied in??
Any insight to how to manage this motor would be greatly appreciated..
Thanks for reading, Mike B - North Carolina
Comments
From this site.
Now the question becomes do I dare try to regulate the speed coil with the HB25 or hardwire the fastest speed and use the HB25 to vary the voltage available???
Mike B.
Almost sounds like a rheostat controller, like a sewing machine.
Sounds like a fun project.
I'm working with some local high school students to build an autonomous cataraft, a dual-pontoon boat. They took apart a $125 Minn Kota trolling motor with a rotating switch handle that provided three speeds and reverse. Once they pulled the switch out and found the two motor wires going down the shaft it was fairly straight forward. The DC motor must have a gearbox and is connected directly to the propeller. This is a great way to get a low-cost, low-speed boat motor.
The circuit is a BS2 => HB-25 => Minn Kota motor.
I grabbed a video a while back. I didn't plan on posting it to YouTube, so excuse the cruddy presentation.
Ken Gracey
Thanks for the reply. I found this trolling motor (WaterSnake Shadow 54DR) brand new in the box EXCEPT no control pedal for $50.00. I am going to use it in a 65" R/C tugboat (www.2tugboats.com). I stripped it all down and have discovered the following.
To the motor there are six wires, two big wires (Red/Black) which are no doubt th main power leads. Four smaller wires (18-20 guage maybe) that I assume are the speed coil wires. A document from the mfr of your motor looked like it had the same setup as mine. They indicated that the speed coil "common" was the black heavy wire. (-12vdc) To test the speed coils they reccomended applying 12VDC to each of the four speed coils in turn to see if all the speeds were working.. I don't see how the four speeds are selected in my motor?? Also there is a pot on the control pedal to fine tune the speed.. I assume it is in series with the selected speed coil??
This motor also has a "steering motor" that simply applies 12vdc to the two leads of this steering motor. I may or may not use this item as it is in a rather large box that also doubles as the thrust bearing for the vertical shaft. We'll see.
So what do you think Ken, hardwire one coil and use the HB-25 for control??
Towards the end of your video you (or someone) picked up some sort of module with several wires attached. Was that the selector for the speeds??
Seeing as I want to control the motor 100% with the HB25 can't I simply find the "fast" coil and tie it to 12vdc and use the HB25 to control the speed and direction of the motor and forget the other three coil leads??
(By the way, this will be a Propeller controlled R/C unit using Xbee modules on both ends)..
Thanks again..
I looked up the motor and from what I can find it looks very similar to a Minn Kota motor, almost the same way every lawnmower looks the same. If you go into Lowe's these days you'll see that they're nearly identical except for different brand names that are plastered on them. I don't even need a lawnmower but I couldn't help getting a closer look last night.
Here's what I'd do: abandon the "steering motor" functions and replace it with a servo, if you really want steering. Some of the hardware might compromise the look or feel of your tug, and I imagine you want nicer proportional steering with a simple interface that's a little more friendly to the microcontroller. Find the DC motor's power/ground leads and connect it to a small power supply, maybe 3-6V at first to verify that you've found the right wires. Turn it up until the motor turns - switch the leads and watch it go backwards, and then wire the whole thing to an HB-25 and Propeller. Forget the other three wires for now.
In my video, that thing I picked up at the end was the speed selector. It was connected to the handle and was really a multi-position switch with some kind of electronics described above to reduce the speed or duty cycle to the motor. I didn't take any time to dig any further. I admit I'm far more of an experimenter than engineer (and my primary job around here is business) so when I stray beyond spreadsheets I'm usually working fairly quickly to see the results, sometimes damaging a bit of hardware along the way.
So, hook 'er up and let us know how it works!
Ken Gracey
I has a sneeking hunch they were similar. I downloaded a "service" document from the Minn website and saw the wires mentioned and how to test the coils. There are four wires in a small square plug going into the motor shaft and the two biggies. I assume with a three speed "transmission" that one of the wires is some kind of common.
I'll try the power up here maybe this evening and see if all the magic smoke bellows forth!!..
By the way, you hit the nail right on the head regarding the lawnmowers (riding type) being of the same manufacturer, you are correct. I work for a trucking company here and we haul ton and tone of mowers from, are you ready, "Electrolux" who makes Craftsman, Troy built, Yard Machine and a host of other brands.. Same machine, different name...
I'll let you know how much magis smoke I set free this evening...
Mike B.
Funny, I was actually referring to the riding mowers when I made that comment. They have the same engine, same electronics, etc exactly like you pointed out. Choosing one is a matter of picking your favorite color!
Well, it's evening in North Carolina. Did you get this figured out?
Ken Gracey
Well, yes and no. I don't have a variable power supply to try the motor out so I tried to hook it up (touch the terminals) to a car attery and it INSTANTLY got super hot on the motor terminals and actually burned the tip of one finger a bit. The specs say the 54 lb model is rated at 12vdc@48 amps. It may be that because I was only holding the motor cable terminals to the battery terminals there was a big voltage drop at the terminal junction that caused them to get so hot. If that is normal current draw I doubt I'll be able to use the HB-25 to control it. When I get home from work this evening I'll try with jumper cables and see what happens.
That small cable that goes to the motor with four wires, assuming a three speed transmission, do you think the fourth wire is a common??
I kinda of thought about dumping the steering motor as you suggested and using a conventional rudder with a servo. In fact I was thinking of using something like a pair of Graupner "Speed 900" motors and twin propellers. (Brass type, not silicon...)
Tha adventure continues..
Mike B.
"That small cable that goes to the motor with four wires, assuming a three speed transmission, do you think the fourth wire is a common??"
I found some wiring diagrams on the motor and controller and discovered that the four wires aren't three speeds and a common but a single, variable speed motor. Three of the wires hook up to a pot and the fourth wire is connected to the negative side of the motor itself. Looks like duck soup. I have a 5K pot laying around and going to try that.
@Ken. I found a 113 page service document on just about everything the mfr of your motor makes. I can forward the PDF to you if you are interested..
Mike B.
I found a document that shows a pot as speed control for the motor. I hooked up a 5K pot and it works like a charm going forward. Reversed the main power leads and it was not happy!!
One end of the pot is hooked to the negative lead of the motor internally. I'm wondering if I hook the grounded end of the pot to the positive lead of the motor if that will make it run in reverse?? In other words switch both the main power leads and the one end of the pot at the same time?? I'm now a little reluctant to try this without some adult supervision...
What say ye coach??
Mike B.
This motor has a speed coil that uses a pot for speed control. Anyone know how to make the thing run in reverse using this speed coil?? If I can't get reverse to work I may abandon the trolling motor in favor of a couple of brushed Graupner "speed 900" motors with twin screws.. Only trouble there is I can't locate a US distributor for Graupner motors, gotta got to the EU for them...
Any ideas out there??
Mike B.
To change direction you reversed polarity on either the field or the armature winding. Reversing both had no effect on direction.
Watersnake-DR-Foot-Control-Wiring-Diagram.pdf
Watersnake-DR-bow-mount-motor.pdf
Here is the two docs I was able to locate on the trolling motor. The actual schematic shows the wiring when used with the foot control pedal which I don't have. The top portion of the schematic is for the steering motor which is completely seperate from the drive motor. It simply gets +12vdc and turns. That works fine.
The pot has it's bottom lead connected directly to the neg lead going to the motor. I have no oportunity to undo that connection. There are six wires going down the shaft to the motor. Two large wires (red/black) which are the heavy duty power to the motor. There is a smaller bundle with four wires that hook to the pot for speed control.. There are two switches on the control pedal to turn the motor on and off and one to remove power completley to the motor. One of the switches is momentary as long as you push it down. The other does the same thing but latches the power to the motor for "trolling". I see no provision for reversing the motor.
I hope these attachments are good enough as I haven't been able to locate anything else...
Mike B.
I'm not sure if I have made a mistake with the SB3 and SB4 switches, but I cannot see any purpose in having two of them in parallel like that unless they are in different locations. Checked them several times and I think they are drawn as per the original schematics.
It looks like the pot is used to vary the speed by controlling the current in the field winding of the motor so unless you can separate that winding from the armature winding the only way to reverse the motor would be to use a second battery to reverse the current through the field coil.
Ok, that sure is a lot easier to see how it is wired for sure. The two switches do the same thing except one of them is tap it on and it stays on then tap it again and the motor stops. The other switch is for shrt moves and as long as you have your foot on the switch the motor runs...
I suppose I COULD open the motor and see if I can seperate the field coil common from the negative lead. Only thing I am concerned with is maybe not being waterproof when I'm done. Nothing to loose I guess as I can't use it as is..
'll have to take a look at that and see if It can be disassembled easily.. What could go wrong?? lol...
I forgot to mention. S1 is a module with a high current relay on it and a pendulum that opens the power to the motor if the boat should rock too much or turn over. Just a safety switch...
Final question: Is it your belief that if I can get the field coil sererate from the power leads that to reverse the direction of the motor all I need to do is reverse the polarity of the field coil and leave the main power as is??
Mike B.
If that is a standard DC brushed motor that is all it should take. You can test this without taking the motor apart by using 2 batteries or power supplies. Connect the main battery or power supply as shown in the diagram I posted, connect the second battery with the positive going to the black wire, and the negative to the yellow speed control wire. That should make the motor run in reverse.
The second battery does not have to have a high capacity. The field coil draws much less current than the armature. Good luck, and keep us posted.