Forklift battery charger

[GlennG]

I have a customer who purchased a used forklift battery charger. There is no paperwork for the unit, and can't seem to find any on manufactures website. The 208 volt input has a max amp rating of 35.6 amps on the nameplate. I called the manufacturer and gave them the info for the charger and i asked them the recommended OCP size, the tech on the phone told me that it requires a minimum 45 amp breaker, or a 50 if i want. DOes that sound right to anyone? If this was a motor i wouldn't question it, but a battery charger? I have never hooked up a piece of equipment like this before, any input would be helpful. Thanks in advance.

 

[Rampage_Rick]

Sounds right to me. Charging stations for electric cars are assumed to be full duty cycle, and the supply circuits are sized to 125% of the load. I would assume that a forklift would be no different.

35.6A x 125% = 44.5A

 

[GlennG]

i completely overlooked that. makes sense to me! Thanks

 

[DrSparks]

Battery charger = transformer

Battery charger = transformer

A battery charger is basically a transformer/rectifier. 125% of rated current is to allow for the in-rush of current during the magnetic stabilization between the primary and secondary coils of the core.

 

[gar]

140611-2355 EDT

DrSparks:

What is the meaning of
"the magnetic stabilization between the primary and secondary coils of the core"?

.

 

[Rampage_Rick]

A battery charger is basically a transformer/rectifier. 125% of rated current is to allow for the in-rush of current during the magnetic stabilization between the primary and secondary coils of the core.

Many chargers nowadays are going to switched-mode power supplies. Club Car golf carts still use transformers, Yamaha uses SMPS, both are 48V lead-acid. Most electric cars use SMPS for the onboard charger since a transformer would add significant weight.

 

[GlennG]

The model I have is slightly older, it looks like a small transformer more or less on the inside and out. It's right next to the panel, so difference in material is minimal. The main thing was I wanted to make sure the unit hAs the right size protection.