KT Controller Really Waterproof?

jkvt

Active Member
This may be a really dumb question, but is a KT Waterproof controller, with waterproof connectors, actually waterproof. I'm not talking the connectors. I'm talking the box/circuitry. I am planning an upgrade that I'm doing to an NCM Moscow+. The controller for that bike sits near the bottom bracket, which gets a lot of spray from the front wheel. That works well because that controller is fully potted. You pull it off and the it's entirely filled with potting material (maybe silicone). I would love to rig up a way to mount this controller in the same place because it is mostly out of sight/out of mind, but I want to make sure it's protected enough to deal with the spray.

Thanks so much for any help!
 
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You should be okay with the KT, it has gaskets at the ends.
Of course when they say water proof it is only so to a certain amount.
You might be able to find a rating for it somewhere.
 
This may be a really dumb question, but is a KT Waterproof controller, with waterproof connectors, actually waterproof. I'm not talking the connectors. I'm talking the box/circuitry. I have one coming as part of an upgrade that I'm doing to an NCM Moscow+. The controller for that bike sits near the bottom bracket, which gets a lot of spray from the front wheel. That works well because that controller is fully potted. You pull it off and the it's entirely filled with potting material (maybe silicone). I would love to rig up a way to mount this controller in the same place because it is mostly out of sight/out of mind, but I want to make sure it's protected enough to deal with the spray.

Thanks so much for any help!
Not familiar with it... Post a link.
Do you know it's IP rating? That should tell you it's capabilities as far waterproofing.
A quick search if I have it correctly is IP64... So that is decent protection as you described.
IP Rating
Have you considered a better front mud guard?
 
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I say no. They can take a splash of water, but not immersion or a steady drip.

Case 1. I mounted a KT controller on the downtube with the cables pointed up. Water dripped into the cable artea and eventually made its way inside the controller. Even though I eventually turned the wiring around so the wires came from the bottom, and put a cover over the controller tp stop splash frpm the rear wheel, I eventually heard the moroe start groaning on a roide, a sure sign of imminent failure, and the controller was dead the next day.
miniv-controller.JPG


Case 2. The first picture shows how I' mounted the controller on my fat tire bike. Works fine. I did the same for my folder, except I put the case upside down. Water came in via the holes for the cable, and the container acted like a bathtub with no drain. Eventually. I had a 1/4" of water in there that seeped in thru the gaskets on the controller. That motor started groaning too, and zap, the box was dead, I opened it up, found moisture inside, and corrosion all along the circuits that fed the drive transistors.

The new controller arrived this week, and I'll put a a pair of drain holes in the tub,

fatbike-ctrl.JPG nova-ctrl.JPG
 
Like most things, most ebike components are water resistant. Externally mounted controllers always poses a risk of vulnerability.

The best practice (I find), is to ensure that any water which 'could' envelop a particular area is treated to ensure that water or moisture can exit or escape. I've seen some who have insulated controllers but have not taken into consideration heat dissipation.

I'm sure you'll be fine with your setup. Just don't aim a pressure washer at it 😅
 
I say no. They can take a splash of water, but not immersion or a steady drip.

Case 1. I mounted a KT controller on the downtube with the cables pointed up. Water dripped into the cable artea and eventually made its way inside the controller. Even though I eventually turned the wiring around so the wires came from the bottom, and put a cover over the controller tp stop splash frpm the rear wheel, I eventually heard the moroe start groaning on a roide, a sure sign of imminent failure, and the controller was dead the next day.
View attachment 111983

Case 2. The first picture shows how I' mounted the controller on my fat tire bike. Works fine. I did the same for my folder, except I put the case upside down. Water came in via the holes for the cable, and the container acted like a bathtub with no drain. Eventually. I had a 1/4" of water in there that seeped in thru the gaskets on the controller. That motor started groaning too, and zap, the box was dead, I opened it up, found moisture inside, and corrosion all along the circuits that fed the drive transistors.

The new controller arrived this week, and I'll put a a pair of drain holes in the tub,

View attachment 111986 View attachment 111984
Harry your cables look like they have been tampered with. Did you "add" waterproof cables to it?
My cables are solid black coated into the controller with waterproofing caulk applied to the entry point.
 
That's not meant to be your primary means of waterproofing or a reason for not applying a little common sense to you installation. You can't spray it with any protectant and then think it's OK to let it get saturated.
Not picking on Harry.. and I understand why he did so but placing wires up as he did is going to fail eventually if you ride in any weather. Water is notorious for following along wires and into an enclosure
You can use some spray protection but I'd start my protection with some silicone caulk at any vulnerable spot and add a splash guard if possible.
Not placing it in a known bad location works well too.
 
Thanks, this is all really helpful! I'm leaning towards just mounting in a controller box on the frame just to be safe. I don't anticipate biking in a lot of wet weather, but I do occasionally and don't want the rain to get in the way.

Another thought I had is to spray on some spray on bedliner. Just a thin coat. I have no idea how well it would work, or how much it could reduce the capacity for the controller to dissipate heat. In theory it would protect and waterproof and make it blend in better with the bike. I guess an important thing to point out too is this is a 22a controller. I'm going to limit it, with the display, to about 18a, so that should help with the heat a bit.
 
That's not meant to be your primary means of waterproofing or a reason for not applying a little common sense to you installation. You can't spray it with any protectant and then think it's OK to let it get saturated.
Not picking on Harry.. and I understand why he did so but placing wires up as he did is going to fail eventually if you ride in any weather. Water is notorious for following along wires and into an enclosure
You can use some spray protection but I'd start my protection with some silicone caulk at any vulnerable spot and add a splash guard if possible.
Not placing it in a known bad location works well too.
yep silicone caulk around the wires. e6000 so you can remove it if you need to.
 
Thanks, this is all really helpful! I'm leaning towards just mounting in a controller box on the frame just to be safe. I don't anticipate biking in a lot of wet weather, but I do occasionally and don't want the rain to get in the way.

Another thought I had is to spray on some spray on bedliner. Just a thin coat. I have no idea how well it would work, or how much it could reduce the capacity for the controller to dissipate heat. In theory it would protect and waterproof and make it blend in better with the bike. I guess an important thing to point out too is this is a 22a controller. I'm going to limit it, with the display, to about 18a, so that should help with the heat a bit.
Yes to be safe, you could add some water proofing. I wouldn't cover the whole case because the fins need to be exposed for the heat sink.
However if you got some liquid electrical tape, you could just double seal all the edges with a thin bead. This would allow the fins to work AND allow you to gain access to the inside if needed, down the road.
I use plasti dip, Easy to apply and easy to remove.
I purposely avoided a controller case because I am over amp-ing mine.
I also moved mine from behind the triangle battery to under the battery on the down tube for the same heat reason.

 
Found potentially the best option yet. The controller is 131x66x38 or 39mm. 131 becomes 141 when including the mounting tab that comes off the controller. Found some plastic cases on Aliexpress. One is 145x85x40 and another is 155x80x45. Margin of error is "1-2cm" which is quite large. At anyrate... I think I'll grab one of each and see how the controller would fit in them. Total cost for the two is only $13 USD shipped. If they fit, my thinking is to use the screw at the bottom bracket (the one for the existing controller) to mount the box along with maybe a little rigging. There's some rails that could help too. Also put a hole in the box so the wires can come out to run up the inside frame, like they do with the stock controller. Then mount the controller in the box, put on the lid, maybe silicone the seam between the lid and box for good measure, because why not, maybe a small drain hole in case water happens to get in it and be done.

I like the idea of some plastidip or silicone around the edges too, just to be safe.

 
Nice job mounting your controller!
That crack in your frame is screaming for help!!!

To the question on topic, the term "waterproof" might be stretching it a bit. Mine is mounted similar to the one pictured above (wires pointed down), has been subject to major rain downfalls while traveling at freeway speeds loaded in an open utility trailer on quite a few occasions. It's been in use since 2017 and still going strong - but your experience may be different....
 
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Crack!? I think you are looking at a reflection. NO Crack!
My bad. On closer inspection, it was a reflection! Sure fooled me! Still a nice looking install. -Al
 
I have an externally mounted KT controller on my Lectric XP and it's been through a few wet spots and left out in the rain a few times and I've have had no issues with it. See here.

controllerupgrade04b-jpg.125039
The answer is "somewhat".
You can easily make it 100% by adding some sealent to the plate joints AND the wire outlets
 
The answer is "somewhat".
You can easily make it 100% by adding some sealent to the plate joints AND the wire outlets
ALL the connector ends on this controller are “waterproof.”
ALL wires leaving this controller are gel sealed.
ALL openings to this controller have a rubber gasket.
While I wouldn’t suggest immersing it in water, for all practical purposes, it’s “waterproof.”
 
ALL the connector ends on this controller are “waterproof.”
ALL wires leaving this controller are gel sealed.
ALL openings to this controller have a rubber gasket.
While I wouldn’t suggest immersing it in water, for all practical purposes, it’s “waterproof.”
You can leave it like that, but you risk that the job wasn't done correctly.

The sealant will cost you all of 10 cents and 10 minutes !
It's your controller, it up to you to decide if that's too much trouble to guarantee it's waterproof.
 
I hate to break the news here, but this KT case, with the end caps removed, splits lengthwise. Point being, there are 2 unsealed openings/seams that are pretty snug. You aren't going to see them until the end caps are removed and you pull the halves open. No big deal in water spray, but hardly waterproof....
 
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