Minelab CTX 3030 Aa Battery Pack Will Not Work On GPZ 7000

[Steve Herschbach]

I was thinking of rolling aluminum foil up tight to diameter of AA and cut to length to replace a couple cells.

[Qld Sandy]

I don't know Dave, as I haven't got a CTX battery here. The AA holder is definitely side by side as I had a look at the small circuit board in one to confirm this. Some of the pins in the detectors may be joined internally?

If it won't work then I'm guessing there is a valid reason behind it.

Cheers.

[Steve Herschbach]

Perhaps the GPZ and CTX Li-Ion packs use one pin set. The CTX AA set and the CTX itself may employ the second pin set to direct to a regulated circuit especially for the higher voltage ?

[DDancer]

Hi Dave,

That is from my website, or should I say was, as I have modified the item info.

I'm not sure where I got that info from, and have put some holders into stock on the basis, but have checked just now as I saw this thread and they are not compatible with the GPZ from what I see.

I also fitted 8 x AA's into a holder and the GPZ doesn't fire up. Further inspection shows that the CTX AA holder (and presumably the battery also) has the positive and negative pins side by side at one end, and the GPZ battery has the positive and negative at opposite ends of the pin socket.

I don't want to be the goose that modifies a CTX holder and finds the GPZ lets the smoke out.

I must apologise for the incorrect info and have modified the item to reflect this.

Cheers.

If what I just read is true and the pin out of the AA adapter is different than the LI battery for the GPZ then the GPZ lacks an internal regulator that the CTX has hence the AA does not work.  I have various electronic devices that we install in aircraft that are set up with pin outs for different input voltages, ie 12vdc, 28vdc 400hz AC and so on.

The GPZ just simply was not designed the same as the CTX for battery types.  This is something ML either overlooked or decided not to incorporate~ the AA battery pack.   LI's have a better performance over time than do NiMH or Alkaline and given how sensitive the GPZ is that may have been a factor to prevent complaints about lousy performance due to low batteries.

A thought.

 

addendum: Thinking on it a bit the relative sizes of the CTX and GPZ packs as well as overall time of use between recharges also suggests to me that the GPZ use's a lot more power compaired to the CTX.  AA batteries were probalbly also ruled out because the GPZ would eat them like candy.  For the same amount of punch in AA's I'd guess you'd need 16 for a GPZ to last a while.... its already heavy   I don't think anyone would want a pack as big as the super size pack of AA's one gets for Xmas so the kids can play with their toys.  Hahh!

[Reno Chris]

AA batteries were probably also ruled out because the GPZ would eat them like candy.

 

I am guessing that is likely the case. Even if through alterations and rigging you could get the AA battery pack to work on the GPZ, it would not last long. The 3030 Li battery pack, which lasts a good long time on the 3030, lasts not more than 4 hours on the GPZ as the GPZ just seems to consume a lot more amps. I am told the AA battery pack lasts only 3 to 4 hours on the 3030, it would be probably well less than 2 hours, maybe closer to one hour on the GPZ. Enough to get you through the end of a long day if your battery ran out, or enough to allow you to dig that last good sounding target you were digging when the battery died, but not a lot more.

[Steve Herschbach]

An hour would suit me just fine if that was all it gave me. Sometimes all you want is that one hour more.

That said, I will leave it to others to mess with. Presumably with some rewiring and a different battery configuration a person could use the shell to make a backup battery pack, and I am sure somebody will. Just not me. It was one thing to buy a cheap shell to employ AA batteries I have piles of anyway. It is another thing entirely to have to rebuild it and be the guinea pig with the 10K detector. Something tells me going that far would void a detector warranty so I officially give up on this idea. It looks like for the moment the only available battery backup for the GPZ is the smaller CTX 7.2V 34Wh batterry until the full size battery is available in the next couple months.

[Gold Seeker]

I think that someone with a GPZ700o should contact Minelab too see what they have to say about this and clarify, they do say that the CTX battery will work with the GPZ so that would lead most to believe that the AA holder for the CTX will work as well since Minelab has never said the AA holder shouldn't be use with the GPZ.

[gollum]

Folks,

 

Here is your easy remedy;

 

 

It is a 22mm x 17mm DC Voltage Regulator. It has a little potentiometer to adjust voltage from 4.5v - 28v DC. It will handle up to 3amps of load. My guess is that the GPZ has a little circuit breaker built in that trips when voltage over a certain level is applied. Because it is adjustable, you can play with it until you find out exactly what that threshold is.

 

DC Voltage Regulator

 

Very inexpensive and will 99% fit inside the battery holder..

 

Mike

[gollum]

G'Day Dave,

 

Sometimes companies are in a hurry to get a product to market, and don't initially provide a good source of ancillary equipment. I think that might be the case with the GPZ. A $10,000(US) detector hits the world market with NO accessory coils available? You would think they should provide several coils in varying shapes and sizes to accommodate the type of detecting and terrain almost anybody would encounter. Where is the 4"-6" elliptical for those heavily brushy areas?

 

When that happens, its up to the end user to find ways to make things work in the interim, until the factory catches up.

 

Take Care - Mike

[DDancer]

No spare parts here in the US either unless you want to buy a second Z and cannibalize it   To expensive to experiment on as well.

 

Reno Cris pulled a relevant statement out of one of my posts that pretty much sums up using AA's.... the Z will likely eat them like candy.

As to using the AA holder of a CTX someone will have to confirm the pin out for power on that holder and if its true that it pins out for power differently than the LI battery pack then you'd have to modify the holder as well as install the regulator.

  Now make a measurement from the stock battery for power draw then calculate how many AA's it'll take to deliver the same battery depth for the Z.

Course you don't have to use the stock LI battery, it'd be a bit of a pain adapting it, you can just be real careful with a bench power supply as well for the measurement.

 

Note if the pin out for power is not different and the Z simply does not like the power input it probably has to do with a simple power test circuit in the Z that looks at the power source and says go or no go before allowing the detector to turn on.

 

Me,  I'm just going to buy the CTX Li battery with its warranty.  Maybe I'll play with a  power supply option after I get back from OZ this year.