24LikesDischarge bank build?
01-25-2019 | 10:06 AM
#31
Tech Master
iTrader: (6)
Joined: Dec 2015
Posts: 1,418
From: San Jose CA
My resistors came in today! Just need to figure out something to mount them on, fans and heatsinks are in order also. I will take pictures of the build and try to make it clean as possiable!
Was thinking of the wiring and probably going to straight wire the fans direct to the power supply. Main reason is because when the battery gets lower and lower voltage the fans spin slower, any input on this?
Thanks!
Was thinking of the wiring and probably going to straight wire the fans direct to the power supply. Main reason is because when the battery gets lower and lower voltage the fans spin slower, any input on this?
Thanks!
https://www.ebay.com/itm/Thermostat-...frcectupt=true
My fan was 6V, so I also have a voltage regulator that steps down the 12V. Thermostat switch is in-between 3rd and 4th resistor from the fan side, as my fan is mounted on one end and blows across the heat sinks left to right..
01-26-2019 | 03:29 AM
#33
Tech Lord
Joined: Aug 2007
Posts: 14,052
From: Holland
Almost the full battery voltage will be over the resistors. So you do need fans working at that voltage. With 2S that is simple because 5 or 6v fans can be found (you only need a resistor or a few diodes to lower the voltage). With 1S that is not that simple.
But from own experience I can tell you that is no good idea. When the cooling stops when the discharging has ended the remaining heat will heat up the while system a lot. I finally decided to give the fans a continious voltage.
The idea of a temp switch is better but in the world of PC fan controlers there are even rpm regulated controlers to be found
https://www.ebay.co.uk/itm/PWM-4-Wir...8lY0:rk:4:pf:1
But from own experience I can tell you that is no good idea. When the cooling stops when the discharging has ended the remaining heat will heat up the while system a lot. I finally decided to give the fans a continious voltage.
The idea of a temp switch is better but in the world of PC fan controlers there are even rpm regulated controlers to be found
https://www.ebay.co.uk/itm/PWM-4-Wir...8lY0:rk:4:pf:1
01-26-2019 | 04:01 AM
#34
Tech Master
Joined: Jul 2009
Posts: 1,416
From: Deep South Texas
Heat Soak..
like when you turn off your car engine... heat continues to build.. for a limited amount of time..
same with engine turbochargers... a cool down time is needed.
but in electronics... even a few seconds can destroy..
and with fet's... thermo runaway..
like when you turn off your car engine... heat continues to build.. for a limited amount of time..
same with engine turbochargers... a cool down time is needed.
but in electronics... even a few seconds can destroy..
and with fet's... thermo runaway..
02-13-2019 | 08:26 AM
#35
So I got all my parts in and put this bank together,
100 watt 1 ohm resistors. 5 total
running the positive wire through the bank for my X6 Charger, I can only get about 4amps of discharge?
Im not sure if I did something wrong or there is a problem with the charger?
01-06-2021 | 09:42 AM
#44
Tech Lord
Joined: Aug 2007
Posts: 14,052
From: Holland
01-16-2021 | 10:55 PM
#45
Tech Master
iTrader: (20)
Joined: Nov 2020
Posts: 1,874
From: Idaho
Putting together parts for my resistor bank. Have 5 resistors on the way. Picked up four fans and this heatsink.
I purposefully bought it to be wide enough that the wiring would all be narrower than the heatsink.
Two thoughts, I might want to get a couple bigger fans for the fin side. Is there anything I may have overlooked on the downside of using a heatsink wider than the ends of the resistor wires?
I purposefully bought it to be wide enough that the wiring would all be narrower than the heatsink.
Two thoughts, I might want to get a couple bigger fans for the fin side. Is there anything I may have overlooked on the downside of using a heatsink wider than the ends of the resistor wires?