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Discussion Starter #41
Nice Batttbridge - looks better than I expected from your description

The size of the resisters sets the sensitivity

I used the LED's with bezels - straight through my dasboard


Thanks, :D:D:D

Yup, pics/videos help explain/show things - tremendously


Is your BattBridge on full time?

...or can you turn it off? (when not in use)

...like with a toggle switch? (dpst)

...or by the ignition? (with relays?)
 

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Hi
I have contactors in both of the battery connectors so when I switch my car OFF there is no voltage at the Batt Bridge
 

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Discussion Starter #43
Hi
I have contactors in both of the battery connectors so when I switch my car OFF there is no voltage at the Batt Bridge

Dual contactors, Kool!

Double Safe :D

What voltage is your vehicle operating at?

Does your BattBridge show when the batteries are going low or "dead" like the description says?


"The Batt-Bridge is about as simple as you can get; that's why it is so inexpensive. If all you want is an 'idiot' light to say, "Stop driving, your batteries are dead," I can't imagine anything any simpler. You really don't need dozens of ICs and hundreds of components just to light a light."




I kinda understand the out of balance indication works


"The Batt-Bridge divides the pack in half, and compares the voltage of each half. It lights an LED when one of them is 1v less than the other.If a cell dies somewhere in the pack, it typically causes a 2 volt change. So the Batt-Bridge warns you that a cell went dead. There are two LEDs, so they indicate which half-pack contains the bad cell."


But, if the battery pack starts in balance & is drained evenly

...how does it indicate a "low battery"?
 

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Hi Guys
John - I used four separate Battbridges when I was using four strings in parallel with my old Headways
And yes it picked up when one cell went west so I disconnected that string until I fixed it

You can use it to split your pack into thirds or quarters - or even uneven splits using the resisters so that the "correct" set-up leaves the red LED's off

Functional
The Battbridge will NOT detect a low battery!
 

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Discussion Starter #46
on the dirt bike I actually don't use a contactor at all, I use a manual switch because I didn't want to use any of my power to drive a contactor. One other thing that no one has mentioned is a precharge resistor... this is critical since it allows the capacitor bank in your controller to fill slowly as opposed to creating a huge inrush current. I use a precharge resistor across my high amperage capable marine battery switch for main power on/off. This method is not mistake proof, so a person must always make sure the switch is off before connecting the battery! I need to make some video's of the electric bike but haven't gotten around to it yet!!
Is this the type of hi-amp marine battery switch you use?

https://www.westmarine.com/buy/blue...s-surface-mount--P009_273_004_012?recordNum=2

It seems like it would work well (operate within specified parameters) with a 44.4V (2Kwh section) of a Chevy Volt battery pack

...this one is rated @ 48V, 200A continuous & ~1,000A peak

Any comments or better options?
 

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Discussion Starter #49
What's their duty cycle as a switch?

These likely more robust, can be remote:
https://www.bluesea.com/products/7702/ML-RBS_Remote_Battery_Switch_with_Manual_Control_-_24V_DC_500A

Here are the specs, on the switch I asked about

https://www.westmarine.com/buy/blue...0wxpm0035v&cm_mmc=AF-_-CJ-_-6156817-_-2470763





Specifications
  • Maximum Voltage: 48V DC
  • Mounting: Surface Mount
  • Circuit Breaker Type: Thermally responsive Bi-metal blade
  • Circuit Breaker Class: Type III - switchable/manual reset - trip free
  • Terminal Stud Torque: 75 in-lb (8.47 Nm)
  • Interrupt Capacity, The fault current that a device, normally a fuse or circuit breaker is capable of breaking without damage: 5000A @ 12V, 3000A @ 24V, 1500A @ 42V
  • Minimum Operating Temperature: -40° C
  • Maximum Operating Temperature: 85° C
  • Case Material: Thermoset Polyester
  • Mounting Hole: Accept #10 (M5) Screw
  • Terminal Stud Size: 5/16" - 18
  • Weight: 0.58lb (0.26 kg)
The one you suggested is only for 24VDC & it's just a disconnect switch


I was thinking more like a circuit breaker/main power disconnect switch combo

...to be mounted right on or next to the positive (+) terminal of a 2Kwh Chevy Volt battery section

...& to, possibly, be used as the "main" fuse & the "main" power disconnect

...for servicing, repairs & storage


Is there any type of advantage or disadvantage to using a circuit breaker instead of an actual fuse?
 
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