RXV brake activity w/ 350 controller

[rabbitreborn]

I have found this to be a common problem with conversions from the Dahner controller to the Curtis controller (have not done a 350 amp Curtis yet, but plenty of the "stock" Curtis conversions). I don't know why, but in about 50% of the cases, I found that changing the motor to the new style motor that incorporates the external speed sensor, the problem vanishes.

My belief at this point is that the encoder bearing is the culprit and is causing the controller to somehow feel the cart is in a "roll away" condition at extremely low speeds, which causes the controller to send a signal to the brake to lock up and stop the roll.

[mjroman20]

Do you have an OEM handset that you are able to check the parameters? There are two things I would consider. One is the RPM to speed value this number should be set depending on the gear ratio and tire size, the stock setup I believe should be 331. The second is something I have seen on the Curtis 123x series controls (they are very similar to the 1206AC) When I get a chance to look and confirm I will update this reply. There may be a setting that closes the EM brake when coasting to a stop once you hit a certain RPM. So the controller checks for throttle request and brake request, if both are 0% and the vehicle is coasting, once it sees that speed drop under say 500RPM it will clsoe the EM Brake under the assumption you wish to stop the vehicle or as it was mentioned a roll-away prevention. In any case there should be a way to adjust the RPM value at which this closes or a way to disable it.

[dougs_huntingcart]

Originally Posted by mjroman20

Do you have an OEM handset that you are able to check the parameters? There are two things I would consider. One is the RPM to speed value this number should be set depending on the gear ratio and tire size, the stock setup I believe should be 331. The second is something I have seen on the Curtis 123x series controls (they are very similar to the 1206AC) When I get a chance to look and confirm I will update this reply. There may be a setting that closes the EM brake when coasting to a stop once you hit a certain RPM. So the controller checks for throttle request and brake request, if both are 0% and the vehicle is coasting, once it sees that speed drop under say 500RPM it will clsoe the EM Brake under the assumption you wish to stop the vehicle or as it was mentioned a roll-away prevention. In any case there should be a way to adjust the RPM value at which this closes or a way to disable it.

Yes I have an encoder. Just don't want to start changing things that could create more problems. I would also like to find a manual that provides the details of each of these variables and definitions of what each does. Sure would make adjustments a heck of a lot easier. But one thing at a time.....

[dougs_huntingcart]

Originally Posted by rabbitreborn

I have found this to be a common problem with conversions from the Dahner controller to the Curtis controller (have not done a 350 amp Curtis yet, but plenty of the "stock" Curtis conversions). I don't know why, but in about 50% of the cases, I found that changing the motor to the new style motor that incorporates the external speed sensor, the problem vanishes.

My belief at this point is that the encoder bearing is the culprit and is causing the controller to somehow feel the cart is in a "roll away" condition at extremely low speeds, which causes the controller to send a signal to the brake to lock up and stop the roll.

Sure would be nice to not have to throw another roll of 100's at this thing to make work as its supposed to... hope there's another way!

[cgtech]

Originally Posted by dougs_huntingcart

Yes I have an encoder. Just don't want to start changing things that could create more problems. I would also like to find a manual that provides the details of each of these variables and definitions of what each does. Sure would make adjustments a heck of a lot easier. But one thing at a time.....

the software in the rxv controller was written specifically for ezgo use. there is not a comprehensive list for everything in the ezgo build of the software.

[dougs_huntingcart]

So where is the speed sensor on a stock 2010 rxv? Although I'm not getting an error?

[rabbitreborn]

Originally Posted by dougs_huntingcart

So where is the speed sensor on a stock 2010 rxv? Although I'm not getting an error?

it's a bearing located in the rear of the motor.

[dougs_huntingcart]

Originally Posted by cgtech

the software in the rxv controller was written specifically for ezgo use. there is not a comprehensive list for everything in the ezgo build of the software.

Is there something from Curtis? I mean there's got to be a way for techs to be able to fix these things. If I bring my cart to the shop, there's got to be some manual that is going to point a tech in the right direction to start troubleshooting. No?

EZGO can't expect a tech to get a cart with the problem that I am having, with a product they are producing and selling, and not be able to fix it.

[BobBoyce]

I have seen this before. If the motor brake is on the edge of passing POST during poweron, it will pass and allow you to drive. As you drive, the brake coil heats up and the resistance drops, causing repeated fails (EM Brake OC) due to exceeding 3 amps of brake coil current. This is because the coil is engaged while you drive, drawing current. You can check resistance of the coil when hot and failing, unplug it quickly and test coil resistance. It should be around 25 to 28 ohms. If it's under 20 ohms, that is likely your issue and you'll need to replace the motor brake. Failing to replace the brake when this happens can result in damage to the motor brake output of your controller.

Bob

[BobBoyce]

Originally Posted by dougs_huntingcart

EZGO can't expect a tech to get a cart with the problem that I am having, with a product they are producing and selling, and not be able to fix it.

You would be suprised. I bought a dead 2015 2Five really cheap because a dealership was unable to repair it under warranty. They gave up and provided the customer with another new 2Five. It took me a few weeks to get the parts (following E-Z-GOs advice on what to replace) and it turned out to be something they had overlooked. They had put in a brand new controller and it was defective. I bought and put in a new controller, problem solved. I sent them the defective one and they are supposed to send me a replacement under warranty. I'll have a new spare since they don't accept returns on electrical items.

Bob