72v + users, do you use a pre-charge resistor?

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Alan B   100 GW

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Re: 72v + users, do you use a pre-charge resistor?

Post by Alan B » Jun 13 2012 9:13pm

The high current is not good for the capacitors either.

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GCinDC   10 GW

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Re: 72v + users, do you use a pre-charge resistor?

Post by GCinDC » Jun 13 2012 9:57pm

Youtube channel, 2013 Highlights vid. Ebike Nerdcast.
Giant DH Comp: 20s lipo (11.6Ah), hs3540, Adaptto Mini-E, 900W BMSBattery charger.
GT I-Drive (sold), 20s lipo, 9C, 72V 45A 12FET.

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GCinDC   10 GW

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Re: 72v + users, do you use a pre-charge resistor?

Post by GCinDC » Jun 14 2012 9:35am

these are what i use @20s, fyi.
Youtube channel, 2013 Highlights vid. Ebike Nerdcast.
Giant DH Comp: 20s lipo (11.6Ah), hs3540, Adaptto Mini-E, 900W BMSBattery charger.
GT I-Drive (sold), 20s lipo, 9C, 72V 45A 12FET.

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Re: 72v + users, do you use a pre-charge resistor?

Post by icecube57 » Jun 23 2012 9:21am

Im changing resistors.. they still gonna be 5w but im ditching the ceramic ones and getting the ones you have and making it similar to yours but instead of andersons I will use bullets...

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Tommy L   100 kW

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Re: 72v + users, do you use a pre-charge resistor?

Post by Tommy L » Jun 24 2012 6:42am

I use a 100watt light bulb :)

I plug my Negative leads together, then I put this light bulb in series with the Red + battery lead and Red + Main controller lead wire.
I wait 5 to 10 seconds and then quickly put my two Red+ together, removing the light bulb from the circuit.
Oh, the things we learn here on the ES Forum! :twisted: :lol: I'm running a 128v nom battery pack. This lights up, briefly!

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Re: 72v + users, do you use a pre-charge resistor?

Post by sn0wchyld » Jun 24 2012 8:55am

Tommy L wrote:I use a 100watt light bulb :)

I plug my Negative leads together, then I put this light bulb in series with the Red + battery lead and Red + Main controller lead wire.
I wait 5 to 10 seconds and then quickly put my two Red+ together, removing the light bulb from the circuit.
Oh, the things we learn here on the ES Forum! :twisted: :lol: I'm running a 128v nom battery pack. This lights up, briefly!

Tommy L sends.... \\m//

Image

not a bad idea. You could use a smaller, say 12 volt globe in series with another hunded-or-so resistor, for a easy way to know when things are charged, and that they're working each time you plug in!

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Tommy L   100 kW

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Re: 72v + users, do you use a pre-charge resistor?

Post by Tommy L » Jun 24 2012 1:50pm

sn0wchyld wrote:not a bad idea. You could use a smaller, say 12 volt globe in series with another hunded-or-so resistor, for a easy way to know when things are charged, and that they're working each time you plug in!

Great Idea!

Tommy L sends.... \\m//
http://www.rawvelocity.com

- 4th Hoolagan FS Mtn 9C-2810 with 128v nom 9.2ah A123 40S40P(1.2Kw) - Lyen 18Fet 4115 - 77.8kph :)
http://endless-sphere.com/forums/viewto ... =4&t=39480

- 3rd Catrike 700 Bionx PL350 Velo build
http://www.youtube.com/watch?v=rYdnkaAhVtI

- 2nd 150lbs Pusher Trailer
http://www.youtube.com/watch?v=Q1qTc4sjORY

- 1st Sears NS mtn bike - Rigid 10a drill 800rpm - 2 12v AGM - 1000 watt inverter - 600w dimmer for throttle, wicked torque!

48.2mph/77.8kph Club

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Re: 72v + users, do you use a pre-charge resistor?

Post by nechaus » Jun 26 2012 7:33pm


i do it this way, or do it with the contactor

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Re: 72v + users, do you use a pre-charge resistor?

Post by John Bozi » Mar 23 2014 10:58pm

Would it work temporarily to just plug in a 6s battery first, unplug and then plug in the rest of the batteries. My controller seems to spark very little the first few times I used them, got worse though...

I got to get to the shops to buy all the resistors etc.

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Re: 72v + users, do you use a pre-charge resistor?

Post by TMaster » Mar 24 2014 1:29pm

All I use is a crystalyte 40A key switch with 12AWG modified wires. I've been pumping peaks of over 100A through it for the last 3 years. All I have between the battery and the controller is this switch. 0 problems. no sparks, nothing.
Specialized HR - 75 lb's
A123 26650M1 23S4P(75.9V Nominal) 7500W Peak
Infineon Lyen 12 Fet/45amp controller heavily modded pushing 110 Amps peak
Yescom Motor with upgraged phase wires (Golden Motor/9C replica)

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