Charging different bikes with the same charger. Bad?

Danijel

Member
Aug 13, 2018
54
52
Netherlands
Hey Guys,

Do you think it's a bad idea to charge a Levo and Focus Jam2 with the same charger?

Both use the same plug and the chargers seem almost identically specified.

Thanks!

IMG_20181114_082358.jpg
 

Swissrob

Well-known member
Sep 4, 2018
327
298
Switzerland
Output 42v 4amp is the same so in theory no problems. The only possible issue is how the charger "reads" the battery is full normally this is by a combination of voltage in the battery compared to input voltage so a full shimano battery might be 36.1v compared to a levo at 36.3v. The easy way to test this is fully charge both batteries (with their supplied chargers) and let them rest overnight then reconnect their original chargers to fully top up, rest them an hour or so and then plug in the opposite chargers to see if either battery takes any additional charge. Do this at the same time and both "should" indicate batteries are full but if one charger keeps trying to charge then you may have a problem so I would not use that charger on both batteries. You can also test the "full voltage" with a multimeter (more accurate than an app) to see if voltage is identical on both batteries. Overcharging is more of a problem than undercharging so use the charger which cuts out at the lower voltage and it should be good for both.
 

Danijel

Member
Aug 13, 2018
54
52
Netherlands
Output 42v 4amp is the same so in theory no problems. The only possible issue is how the charger "reads" the battery is full normally this is by a combination of voltage in the battery compared to input voltage so a full shimano battery might be 36.1v compared to a levo at 36.3v. The easy way to test this is fully charge both batteries (with their supplied chargers) and let them rest overnight then reconnect their original chargers to fully top up, rest them an hour or so and then plug in the opposite chargers to see if either battery takes any additional charge. Do this at the same time and both "should" indicate batteries are full but if one charger keeps trying to charge then you may have a problem so I would not use that charger on both batteries. You can also test the "full voltage" with a multimeter (more accurate than an app) to see if voltage is identical on both batteries. Overcharging is more of a problem than undercharging so use the charger which cuts out at the lower voltage and it should be good for both.
Thank you for this very thorough explanation! I have a multimeter so i will check the fully charged voltages after charging them with the same charger.
 

Eckythump

Well-known member
Founding Member
Jan 16, 2018
832
680
North Yorkshire
The RoPD connector is part of the EnergyBus Association push for standardisation. The idea being chargers & public charging stations using the plug are cross compatible.

- www.EnergyBus.org
EnergyBus - Wikipedia

The RoPD is a smart connector which probes the battery BMS via CAN Bus before setting the charger to the correct volts & amps or if not compatible will not supply power.
 

Danijel

Member
Aug 13, 2018
54
52
Netherlands
The RoPD connector is part of the EnergyBus Association push for standardisation. The idea being chargers & public charging stations using the plug are cross compatible.

- www.EnergyBus.org
EnergyBus - Wikipedia

The RoPD is a smart connector which probes the battery BMS via CAN Bus before setting the charger to the correct volts & amps or if not compatible will not supply power.
That's awesome! So no worries there.
 

Eckythump

Well-known member
Founding Member
Jan 16, 2018
832
680
North Yorkshire
I don’t know if you have tried a multimeter as per Swissrob’s suggestion, on the Focus you will not get a reading on the main voltage pins of either the bike or the charger.
I spent a lot of time trying to be able to use my fancy lithium RC chargers for my bike so I wouldn’t have to use an inverter when mobile charging but I couldn’t get it to work without access to the protocol.
 

Danijel

Member
Aug 13, 2018
54
52
Netherlands
I don’t know if you have tried a multimeter as per Swissrob’s suggestion, on the Focus you will not get a reading on the main voltage pins of either the bike or the charger.
I spent a lot of time trying to be able to use my fancy lithium RC chargers for my bike so I wouldn’t have to use an inverter when mobile charging but I couldn’t get it to work without access to the protocol.
I have not tried it yet. Maybe i can get a reading from the Levo battery. I will let you know if i succeed.
 

EMTB Forums

Since 2018

The World's largest electric mountain bike community.

555K
Messages
28,051
Members
Join Our Community

Latest articles


Top