Menu
What's new
Find's Treasure Forums

Welcome to Find's Treasure Forums, Guests!

You are viewing this forums as a guest which limits you to read only status.

Only registered members may post stories, questions, classifieds, reply to other posts, contact other members using built in messaging and use many other features found on these forums.

Why not register and join us today? It's free! (We don't share your email addresses with anyone.) We keep email addresses of our users to protect them and others from bad people posting things they shouldn't.

Click here to register!

Need Support Help?

Cannot log in?, click here to have new password emailed to you

Explorer Power Supply

C

cachenut

New member
I have noticed over the years that both Whites and Minelab detectors work much better when the batteries are very new. I get an extra 4 to 6 inches and the signals are crisp and easy to hear.

So I want to construct an alternate supply for my minelab explorer.

I am sure I can modify the current battery case and detector to take a plug in cable and run this to a hip mount battery cell. All I need do is to add the battery plug into the back of the battery case and punch the right sized hole in the rubber cover that clips over the current setup. This means buying a rubber cover and a new battery pack for when I use real batteries.

No with this done I only need to worry about the type of power cell to use. I believe this means volts and amps but I do not know what amperage or volts to ask for.

This is my big question?

Now with AC equipment amps are not important. I can run a hair dryer or a computer for that matter on an 80 amp circuit or a 10 amp circuit. It doesn't hurt a thing. I just have to meet the minumum required.

Voltage on the other hand is very important. On a 220 volt circuit a lightbulb burns real BRIGHT for about 10 minutes and then blows. Sometimes it goes right away.

But how about DC exquipment. Is voltage and amperage as important or unimportant?

I dont want to burn up my Explorer!!!

Now rechargeable batteries do not cut it.

The copper tops are labeled MN1500 and 1.5 volts. I believe thats 1500 millamps. So with 8 you get 12 volts and 12000 milliamps or 12 amps.

When new the batteries seem to generate 12.6 volts at the back of the battery case. As measured by my cheapo voltmeter. And I expect some more amps too but I could not measure it.

My question for you guys is what voltage and amperage can I safely run into my minelab Explorer?

Is 20 volts better? Is 13 volts the best I could do? Do I need to use only 12 volts and 12 amps?

What gives the extra inches, volts or amps?

I plan to buy a sealed wetcell of relatively small size to mount on my belt. Then I can recharge it ever so often. There is a wide selection now because of all the devices like UPS for computers that use them. An alternate might be two of those coleman lantern batteries the small ones if they were of proper voltage.

I might need to put some sort of electronics in the battery path to adjust the voltage if it is too low. With modern advances I think this just requires a small chip or something.

So if you can answer these questions or enlighten me please let me know. Or if you know someone who might please give me an email and I will contact them.

Your fellow Gopher. cachenut.. miniball@visuallink.com
 
The depth of the detector can not be increased by increasing the power Supply voltage!, the detector will have a regulation circuit built into the power supply , the more voltage you push into the regulator then the hotter the regulator will get!. You would fry the circuits if not careful. I have played about with vlf metal detector circuits some years ago trying different methods to get more depth but all to no avail.
 
What f75uk is telling you is correct. I have thought of having hip mount batteries with batteries removed from the detector handle. If one did that it would be possible to use the correct voltage but batteries with a higher mAh rating (maybe if available or parallel batteries providing a greater mAh rating). My thought was to make the Explorer lighter, actually I don't have a problem with battery capacity (mAh).
 
I do know that depth and performance increases with a new set of batteries. Whether this is caused by increased amperage or increased voltage I do not know. As the battery pack gets used up the peformance drops. If not voltage then it must be amps. I do not have numbers to print them here.

If the power supply has a voltage regulator in it then my minelab battery compartment has one up in the end. Someone said this in the past to me. I do agree that it will heat up when taxed too much.

thanks for helping out.
 
The information in red is taken form a web site somewhere BUT is not entirely correct due to the fact that nimh batteries can actually be charged up to and give a longer operating time at 1.5 volts with a suitable charger( some battery "bank" chargers work well for this purpose):

Milliamp Hour (mAh)

Milliamps Hour (mAh) is important because it's the easiest way to distinguish the strength or capacity of a battery. The higher the mAh, the longer the battery will last. Batteries with different mAh ratings are interchangeable. If your battery is rechargeable then the mAh rating is how long the battery will last per charge.

Milliamps Hour is 1/1000th of a Amp Hour, so a 1000mAh = 1.0Ah

Think of a cars gas tank. Voltage is how much gas is being used, and mAh is the size of the gas tank. The bigger the gas tank (mAh) rating the longer the device will run. If your battery is rechargeable, then think of the gas tank as refillable (rechargeable).

The Explorer will sound off when it is about to shut down due to there not being enough current at that voltage of no less that 9.6 or 10.6 volts DC and for it draw on to drive the Explorer along in what ever configuration it is in.eg:

Running the back light on with a 15 inch WOT coil draws down more current than the stock and smaller coils with out the back light on.
This will equate to a lowered voltage and first. This can be measured across the negative and positive poles of the battery BUT there is still a current left in the batteries that will drive something with less a requirement. Explorer's on board circuitry inside the control box is what determines if the battery pack can dive it. That's where all it's logic is located. You would need the correct amount of voltage that a power source could sustain at a continuous level with what is required by the Explorer in order for it to function properly.

The internal power supply, on it's own separate board, filters and regulates and distributes very precisely how much voltage it will permit into the digital surface mounted chip circuit technology, that is very fickle to too high a voltage increase.


given the type of electronics Explorer uses, I firmly don't believe you'll get an increase in performance of depth and detecting with the Explorer simply by upping the voltage.

In fact, I think in that all you'll do is probably cook it's power supply.believe me when I tell you that the power supplies are not easy to fix and you have to expect to replace one at a cost. I have used alternative power supply sources in the past and still do. One source is a 14.4 volt 4.4 Amp hour hip mounted Gel cell. Works BUT it's not really what I would call the best way to deal with the continuous power supply requirements that has somehow given the Explorer ANY depth increase. I prefer a small bag of 8 spare good quality Alkalines in my pocket and/or in the Explorer battery pack.

Nimh packs have been known to under perform for what ever reasons(usually due to one or two of the cells inside failing)and so have some cheap AA Alkaline batteries. If one goes the it affects all the others with overall performance. Don't go believing that new is always the answer as even a new cell can fail almost immediately. I found that if you are going to use rechargeable nimh's then get a charger that will bring them up to 1.5 volts. That's what's inside the Minelab nimh battery packs, 8 x 1.2 nimhs you get about 12 volts form them at up to 1700 mah.There is a small rectifier circuit inside the battery pack where you plug 15volt AC transformer into. It allows the 8x 1.2 volts to be charged up to average 1.5 volts each. If they were only charged to 1.2 volts then the packs would need batteries like 2000mah or more to last as long as they do.

Maybe you would have been able to input extra voltage into some of the older analogue circuits and get some sort of performance increase but now way with Explorer. I think Minelab have given us the maximum.
 
What you want is a bigger storage tank. Batteries are your storage tanks. Think about a truck with 2 gas tanks...when one gets low, flip the switch to change over to the other tank which is full. Or do what the rest of us do, pop in some new batteries.....If they ever come out with a better battery that can store more hours of use at a certain voltage then problem solved...maybe solar charger on board to keep batteries constantly charged would be good.....but don't mess with manufactures required voltage for your detector.
 
I think your opinions on the subject are all noted. I have talk to Minelab on the issue and the answer I got might surprise you. They recommend the 1.7 batteries such as the Panosonic oxy's or the Sanyo enlope. I believe those are the names, anyway the 1.7 instead of the 1.5. That caught me off guard too. Just goes to show if you ask the right question you get the right answer. You might want to refer this question to Cody in the Explorer Class Room Forum as of why. I'm sure he could explain it better than I could.

Tom
 
I've been running the Explorer XS and EX 2 for the last few years on essentially what would be the equivalent of 8 x AA 1.8 volt batteries given the fact that I also use a 14.4 volt gel cell that if divided by 8 equals 1.8 volts.:surprised:

I still haven't found any improvement in depth. I also note that there is a little component, that might be a thermistor, that's located inside the Alkaline cell pack. Why is this here in series to one of the poles?

There are no written recommendations on than the ones Minelab make, so watch out if you go out of parameter. Unless they categorically state that you can use anything over 1.5 volts you do take a risk. That's okay if you are prepared to take it and as I have BUT may not help when your trying to get your detector repaired.

I think this one will even go over Cody's head. If anyone would know, it'll most likely be Charles(NY). Or maybe their is someone else out their who can help. :thumbup:
 
Panasonic oxys (oxide) or Sanyo enloe (?) (maybe ??ion). Silver oxides are button batteries. Zinc oxides maybe but where can they be obtained?
 
Well the general concenses seems to be I should stay close to 12 volts and not worry about amps. One qualified person recommended 12 volts and .13 amps someone else uses 14.4 volts, all the time.

Several say providing too few amps can damage the machine or burn up wires.

Several responders think I will get no increased performance by an increased voltage. I agree but I think having the pack fully charged all the time increases performancs.

I do agree increasing the voltage will be dangerous and I will not do it but I think I get better performance with new batteries and I want to do this all the time. So I want something that provides 12 volts all the time and does not fall off as far as amps or volts goes for about 8 hours.

Several people say providing an excess capacity of amps as in a wet cell will not harm the detector. Those 12 volt wet cells are designed to discharge quickly so they will provide 10 or 20 amps if asked to.

I wonder if the detector will try to pull that much if it is available? Several responders say no but I still wonder if they are right.

Joe.
 
Your detector will not pull 10 or 20 amps.
Your detector has a lump sum impedance (resistance plus reactance) that limits the amount of current that it will draw. Ohm's Law variation I=E/R indicates that the current pull is determined by the amount of voltage supplied divided by the resistance (load value) of the detector.

The whole thing is more complicated than this, as the detector's voltage regulator is constantly shaving off excess voltage and dissipating power. It is a necessary evil to waste this power in the process of regulating voltage. It is possible that some of the circuits operate on unregulated voltage.

Then there is the factor of internal resistance of the batteries which limits the amount of current they can supply. As the batteries run down, the internal resistance increases , the current becomes reduced, and the output voltage drops. Your detector will continue to operate until the supplied voltage becomes too low to keep the voltage regulator operating.

For example my Sovs operate on just over 50 ma of current....about half of which is used by the transmit side of the coil. The mah (milliamp-hour ) rating of the batteries will indicate how long it will run before recharge is needed. At 50 ma current draw, you divide 50 into the mah rating of the batteries. This tells you how many hours it takes to kill the batteries. Don't know what the drain is on an EXP....used the Sov as an example.

The bottom line is this....stop thinking . Use good batteries and avoid becoming a member of the crispy critter club.

HH
 
Lets see if this pastes okay. I think this battery will do it.
The sellers response to my inquiry.
============================================
I am sorry but we do not carry a 12 volt, .13 a-h battery. The smallest we carry is a 12 volt, 1.3 a-h battery. Did you mean 1.3 instead of .13 a-h? If so, our 12 volt, 1.3 a-h battery is shown below and it sells for $ 8.95. Thanks for your inquiry.

Universal Sealed AGM 12 Volt Battery (UB1213)


Quantity in Basket:none
Code: D5738-AB
Price:$8.95

Shipping Weight: 1.67 pounds

To see it click here. Pics of Batteries


Quantity:

This Battery is a state-of-the-art sealed AGM battery. The advantage of this design is that the battery needs no water additions, can be operated in any position, and can be used in close proximity to people and sensitive equipment. The specifications on this battery are Length 3.82 in., Width 1.69 in., Height 2.01 in., Terminal Config. F1 and Amp Hour Capacity 20 hr. rate is 1.3.
=============================================

This seems to have 10 times the capacity I need and for a 20 hour period. It certainly meets the minimum requirement. I dont guess it would last 200 hours then. 10x20=200. It is rechargeable and about the size of 2.5 packs of cigaretes at 1.7 pounds.

Now if it just keeps the 12 volts for 20 hours at .13 amp per hr. I would be happy.
 
yes....200 hours if your detector uses .13 amps.
Where do you get that .13 figure? seems like a lot as it is about twice what a Sov uses. If that is correct, then Explorers must really eat batteries.
 
Someone I used to know told me. He is pretty reliable. Yes they do eat batteries but they are worth it. I used my coppertops about 10 hours I think before I trash them. I tend to replace them early cause I like the best performance I can get.

But when you look at the dollar per hour cost and all the fun and compare it to the costs of other hobbies, golf for instance, then detecting is a bargain.

Do you think the extra volt or amerpage would hurt my explorer?
 
Running at 12-13 volts should not hurt. 8 AA batteries supply that much.
You will NOT be running at any more current than you would use with batteries running at the same voltage.
You seem to have the mistaken impression that having a supply that can provide more current at the same voltage will supply more current at that voltage. This is entirely false. You could run it on a car battery, and if the detector draws 100 ma on AA batteries, it will draw 100 ma on the car battery also.
HH
 
Thank you very much. I knew this was true for AC but did not know on DC.

Another question. What does the following tell you about recharging and how should I do it and what equipment will work? autobattery charger? How to tell when fully charged? 13volts?

Max. Discharge Current (5 sec.) 15A
Cycle
Initial Charging Current less
than 0.36A Voltage 14.40V ~
15.00V at 20
 
Has to be recharged at about 1/3 amp or less.
Recharge time would depend on how far the battery has drained and what the recharge current is.
A car charger may be too hot.....if it pushes with too much voltage, the charge current could be too high and blow up the battery.
See what the mfr would recommend. This looks like an equipment battery...as such, the equipment would have a charge ckt built in.

Personnaly, I would use my radio shack power supply (3amp max @ 13.8v) and monitor the charging current with a meter. If the current were too high, I would add some resistance in line to get the current into a safe range.

HH
 
You must log in or register to reply here.
Top