Do-it-yourself
"Brute Force" Discharging Option for your HI- IQ charger
This add on device will safely let you discharge your 6 cell packs at 45 amps without overheating your Victor HI-IQ charger. Preliminary tests at 45 amps, ( Yes I said 45 Amps ! ) showed heat on the unit was no greater than charging a 6 cell battery at 4 or 5 amps!!
This test was conducted on a non-modified charger ! ( No extra FET's added and No Cooling Fan ! )
What the IQ Booster unit does:
One of the things as you well know is when you are discharging a battery at high currents, the Victor charger heatsink becomes very hot! and you must use a fan to control the heat build up on the heatsink. What you are doing is dissipating all the power across the junction of the discharge FET's.( P=E x I ) By building the Booster unit you are creating a different place external to the Victor charger to dissipate the power in. ( This becomes a series circuit for those that want to work out the numbers.)
All you have to do is buy an external load..
Go to http://www.digikey.com/ and buy this 300 Watt High Power Resistor.
part number AVE300-.10-ND
The next thing is to connect one end of the resistor to the Positive wire of the Nicad and connect the other end of the resistor to the motor / load negative connection on the charger..(yes this is correct as this is the path of least resistance inside the charger) The negative end of the battery connects to the Nicad negative connection on the charger. Next is to place the resistor in a box, with a fanblowing over the resistor as this becomes the place where the power gets dissipated across.
Yes I know that it depends on what current you are discharging at as how much power is placed across the resistor.( Remember: A series circuit with the charger and resistor. )but this is a goodcompromise ( the resistor value used )as I have not actually measured a True IQ Booster with an Impedance Bridge...As I mentioned above, it sure makes a difference in heat developed on the Victor heatsink, and also reduces the amount of power the FET's have to handle during discharging.
Try it!
Remember: The sense leads from the charger MUST! be connected right at the nicad battery or as close to it as possible for the best results.
Another note: You can leave the Booster unit connected and charge through it too!
When constructing the unit use 2 runs of 12 gauge wire and keep your wires as short as possible..
Completed Booster unit.
Booster Connected to Victor Charger.
To access the higher discharge currents you must remove the top cover of your Victor charger and find the option # 2 position on the PC board.
It is to the right of the keyboard, then you must install a wire jumper in this location. When you power up the unit, the bottom line of the display
will say " I'm Booster IQ", if you are using the Super IQ 2 software. If you are using the IQ 3000 it will display the normal screen. But when you go into
the discharge mode you will be able to accessup to 99 amps for the discharge current.
This is for Informational Purposes only!
I assume NO Responsibilities for any damage incurred on your unit from this modification!