Using Car Booster Pack for Different Applications

[Peter_wadley]

Hello

I bought a motomaster 22AH Lead Acid Booste car Booster Pack with 700 CCA

I wanted to use it for boosting my car in cold weather AND other things such as power a 1000 WATT inverter in cases such as a power failure.

Problem: The booster only activates if it senses a voltage of > 3.5 Volts on its leads...

When it 'sees' a car battery on its leads a relay connects the battery to the leads...

Question: Could I purchase say a Small 2AH Lead acid battery to connected to the booster in order to activate the internal relay then ... in parallel, connect the Inverter?

Would the booster just charge the Lead Acid ... while supplying power to the inverter for me to use? What happens when the battery becomes fully charged?

Peter

https://www.canadiantire.ca/AST/browse/4/Auto/SolarPortablePower/PowerPacks/PRD~0111591P/Motomaster%252BEliminator%252B700A%252BBooster%252BPack.jsp <--------- THE BOOSTER

 

[Peter_wadley]

Also I was wondering how I would calculate how long the battery would last power say 500watts ..

given that it is 22AH ..

 

[MikeMl]

Nominally 1A for 22Hours. Look at these discharge curves for a**broken link removed**. This one will not supply 700CCA, but its capacity is similar to the one used in your box.

I am a ham radio operator, and wanted a portable battery pack to power my emergency "grab and go communications" kit. I took apart one of these boxes and modified it by mounting some anderson PowerPole connectors (the standard connector adopted by all emergency comm folks) right on the portapak.

I bypassed the voltage sensing circuitry and connected my connectors directly to the battery (through an appropriate fuse). The unit is other wise still usable for jump starting.

 

[Peter_wadley]

Thanks for the reply MikeML

Can anyone explain what would happen if I did try connecting a smaller SLA battery to activate the relay?? The package is pretty rugged and looks hard to open...

Would the boost just charge the smaller SLA until it reaches the same voltage as the booster battery??

 

[MikeMl]

You would still have to open it up to parallel the small battery with the built-in charger. Paralleling SLAs is ok as long as they use the same internal chemistry, or ones made by the same maker. I would not parallel an AGM with a VRLA or with a flooded-cell Lead Acid battery.

If it is just to trick the PortaPak into starting up, you could likely use a momentary pushbutton, a diode, and a 9V alkaline cell. The diode would prevent back-feeding the 9V battery once the Pack starts up...

 

[Peter_wadley]

hello

I tried using the 9V with a diode but it did not work

I used the following setup:

------ + ----- |> -------------------- POSITIVE LEAD OF BOOSTER
9v DIODE
------ - -------------------------------NEGATIVE LEAD OF BOOSTER
hmmmmmmmmmmmm

 

[MikeMl]

hello

I tried using the 9V with a diode but it did not work

I used the following setup:

------ + ----- |> -------------------- POSITIVE LEAD OF BOOSTER
9v DIODE
------ - -------------------------------NEGATIVE LEAD OF BOOSTER
hmmmmmmmmmmmm

Mystery. I would have thought that the 9V (-0.6V for the diode) would have supplied enough current to "start up" the booster?

 

[Peter_wadley]

I also tried it with a 12 V hobby power supply..

Rated at 3 A ...

Still nothing ..... works with the car battery though