July 23, 20196 yr I have a Voilamart 250w rear hub & the controller has only one level of PAS. Is there any way I can fit an LCD to this to give me better control, or do I have to buy another controller with LCD ?
July 23, 20196 yr The controller will be anologue so you need a digital type with 5 levels of PAS, KT with lcd3 is the most user friendly type on the free market. Buy a complete package of controller, lcd, PAS, throttle and brake cut off/levers for about £110 or mix and match compatible components. Old syle wiring kit https://www.aliexpress.com/item/1956544492.html?storeId=738588&spm=2114.12010612.8148356.59.2eb94e3cpl8PLW Or Julet kit https://www.aliexpress.com/item/33023594311.html?storeId=738588&spm=2114.12010612.8148356.48.2eb94e3cpl8PLW If you want a low power kit go for the 6 mosfet 14a kits and not the 9 mosfet 22a ones. Not forgetting you can reduce the current with all KT controllers by at least 5a. Edited July 23, 20196 yr by Nealh
July 23, 20196 yr Author Thankyou! Actually looking for something a bit cheaper. Would this be compatible. https://www.ebay.co.uk/itm/Electric-Bike-Battery-Speed-LCD-Display-36V-48V-350W-E-Bike-Accelerating-Control/123828722403?hash=item1cd4c45ae3:g:jNgAAOSwVZBdElGO
July 23, 20196 yr It is one of the Brainpower controller kits they are a bit temperamental to set up by all accounts and low power 13a. You still need a Pas and a throttle if you want one, if you have these then simply solder the correct wires together and heat shrink as the connectors will likely not match. KT is the best most used after market system available.
July 23, 20196 yr You need to check whether your motor cable has he white wire in it. If it doesn't, you'll need a separate speed sensor for the LCD to show speed.
July 25, 20196 yr Author Does anyone know if the Voilamart 250w motor controller is sine wave or square wave ? Also - How much difference would it make to have a 13A controller as opposed to 15A ( I have a 36v 15 Ah battery )
July 25, 20196 yr Tell us how many pins the motor wire connector has, 3 is unsensored/Sq wave & 8 or 9 is sensored/Sine wave the 9th wire being for int spd sensor. Controller current rating depends on the cells used inside and their CDR (current discharge rating) 15a will give a little more watts output.
July 25, 20196 yr Does anyone know if the Voilamart 250w motor controller is sine wave or square wave ? Also - How much difference would it make to have a 13A controller as opposed to 15A ( I have a 36v 15 Ah battery ) 15% difference in power (torque) and battery consumption. .
July 26, 20196 yr Author 8 wires so must be sine wave. It has quite good torque at the moment & don't really want to lose any of that so I guess I'll be looking for a 15A + controller. - Thankyou all !!!
July 26, 20196 yr If changing and you opt for KT go a bit more and 17a you can always dial the current down. 8 wires is indeed sinewave you would need an external speed sensor which you probably already have wiring it in is easy as KT have a separate wheel speed sensor connector.
July 30, 20196 yr Author Thankyou ! Also it takes about 6-7 revolutions for my PAS to cut in. Is this normal ?
July 30, 20196 yr KT & Luishi controllers are pretty much instant 1/8 of a rotation, how quick PAS engages is down to the programming mainly.
August 9, 20196 yr Author Thanks ! Have fitted KT controller & it works very well. Only about half a turn for PAS to cut in. Also throttle does not affect the PAS I can use either or both. - There is a grey wire ( EABS ) something to do with flexible braking - what is that ?
August 10, 20196 yr Author I think it might be for brake regen which doesn't happen with geared hubs. Thanks
August 12, 20196 yr The 6 fet ones can get very hot (to hot to handle at times) and need to be in free air for cooling, if they are in a bag of any kind then there is no air circulation The ali case acts as a heat sink for the mosfets, a combo of slow speed and high power esp on hills causes the mosfets heat to rise which is why the case becomes a hot potato. You can add extra heat sinks to the case to try and help, add a small 5v fan or two, place it in free air or attach it to the bike frame and use the frame as a heat sink. When mosfets reach their max temp they cut power until cooled (thermal cut off) and the bike is powerless it may take 5 -10 mins for them to cool sufficiently for power to flow again. I do use 6 mosfet ones and have no issue on my commute/town workhorse, on my 700c Boardman ( more of a touring set up) I had issues and opted to use a 9 mosfet larger controller for better heat control.
August 14, 20196 yr Author The 6 fet ones can get very hot (to hot to handle at times) and need to be in free air for cooling, if they are in a bag of any kind then there is no air circulation The ali case acts as a heat sink for the mosfets, a combo of slow speed and high power esp on hills causes the mosfets heat to rise which is why the case becomes a hot potato. You can add extra heat sinks to the case to try and help, add a small 5v fan or two, place it in free air or attach it to the bike frame and use the frame as a heat sink. When mosfets reach their max temp they cut power until cooled (thermal cut off) and the bike is powerless it may take 5 -10 mins for them to cool sufficiently for power to flow again. I do use 6 mosfet ones and have no issue on my commute/town workhorse, on my 700c Boardman ( more of a touring set up) I had issues and opted to use a 9 mosfet larger controller for better heat control. Thanks! Is that a square wave or sine wave 9 FET controller - not sure which is best?
August 16, 20196 yr Author Does anyone know the gear ratio of a voilamart 250w hub, & the number of magnets?
August 16, 20196 yr Does anyone know the gear ratio of a voilamart 250w hub, & the number of magnets? If it is to ascertain the P1 value simply use GPS to calibrate P1 by matching the speed read outs. Set lcd to 25km/h and P1 to 87 to begin with. If it under reads the GPS raise the P1 value, it it over reads lower the P1 value unti it is nearly spot on.
August 26, 20196 yr Author Voilamart 250w hub, KT 20A controller & LCD3. System works fine but I can't get my speedometer to work accurately. I already have an old speedo on the front wheel for reference. I have adjusted the P1 value to 88 which seems to coincide with the old speedo up to 18.5 mph while pedaling. If I go - say 22mph( old speedo ) the speed on the LCD reads 18.5 mph & won't go above it (while pedaling ) If I stop pedaling, then the LCD coincides with the old speedo. They both seem to coincide up to 18.5 mph. Why does the PAS interfere with the speedometer at all ?
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