NCM Prague Battery

[David Gafford]

Hi, I've managed to get a new battery shipped to the UK from France at great expense for my NCM Prague. Annoyingly it doesn't work. The sender has said try changing the fuse, but I don't know how to do that as there is no fuse cover. I'm not even sure there is a fuse. Does anyone have any ideas? Thanks, Dave Gafford.

 

[gromike]

Have you taken a voltage reading of the discharge and charge ports? Sometimes the bms shuts down the battery. I've used a force charge (which I assume supplies a sufficient charge voltage) to turn the bms on. I have a Grin Satiator charger that will do this.

 

[David Gafford]

Have you taken a voltage reading of the discharge and charge ports? Sometimes the bms shuts down the battery. I've used a force charge (which I assume supplies a sufficient charge voltage) to turn the bms on. I have a Grin Satiator charger that will do this.

Hi thanks for your reply. I've tried to check the voltage but as it won't turn on there is no reading.

 

[6zfshdb]

There have been reports about dirty switch contacts causing this problem:

NCM battery problem

I have a Moscow Plus, the battery will not switch on either on or off the bike, the charger shows fully charged.

forums.electricbikereview.com

Another thread on the issue:

NCM Battery won't turn on unless "jump started"

Hello, I have a NCM Prague with about 400km on it. When the bike has not been used for a period of time the control panel on the bike will not turn on the battery/bike. The battery capacity button also doesn't turn on the battery/bike or show the battery capacity. I've never timed...

forums.electricbikereview.com

You might also try looking in the NCM sub forum for similar issues:

Known Issues & Problems with NCM Products + Help, Solutions & Fixes

No Ebike is perfect, this is a thread dedicated to sharing known issues or problems with electric bikes from NCM as well as any help and solutions you know of. Sometimes that means a DIY fix and other times it can mean a recall, software update or part replacement by a dealer. Please be...

forums.electricbikereview.com

This may help locate the fuse:

AI Overview
Learn more

For NCM Prague electric bikes, the battery fuse is typically located inside the battery casing, near the main power connection, and often requires removing a protective cover to access.

Here's a more detailed breakdown:

• Battery Compartment: The fuse is usually integrated into the battery pack itself.
  
  
• Inside the Casing: You'll likely need to remove a protective cover or casing to access the fuse.
  
  
• Near Power Connection: The fuse is often positioned near the main power connection between the battery and the bike's electrical system.
  
  
• Controller Box (Alternative): In some models, the fuse might be located in the controller's housing.
  
  
• External Fuse Box (Premium Models): Some premium models have a dedicated external fuse box for easier access.
  
  
• Check for a 30 amp (green) blade fuse: As per the Revibikes Owners Forum, the battery fuse is a 30 amp (green) blade fuse, and is located inside the black case tucked down the inside of the case at the opposite end from where the charging port and switch are located.
  
  
• Semi-integrated batteries: These batteries have two fuses: a 10 amp and 40 amp, located at opposite ends of the battery.
  
  
• Removable or soldered fuses: Semi-integrated batteries can have either removable automotive-type fuses or soldered-in onboard fuses.
  
  
• Check for a 5a charge fuse: Some batteries have a 5a charge fuse, usually at the bottom, and a 15a-20a discharge fuse at the top.
  
  
• If the headlight does not work: Check the battery 30amp (green) blade fuse.