BatteryMINDer BatteryMINDer 36271 User manual

Rev. D-120913 P/N VDC36271/48021-MNL
READ AND SAVE THESE
INSTRUCTIONS
VDC Electronics, Inc. •155 W. Carver St., Ste. 2 • Huntington, NY 11743
www.BatteryMINDers.com • [email protected]
BatteryMINDer®
36-Volt 36271 and 48-Volt 48021
Battery Maintainer-Desulfators
INSTRUCTION MANUAL*
All Models Include:
• ATS Temperature Sensor (installed)
• Ring Terminals with 15A Fuse
• EZC-01 EZ Connector + Mounting Screws
• Designed to be used with your vehicle’s “stock-bulk” charger.
The BatteryMINDer takes over when the original supplied charger
shuts off. See the accompanying addendum for more details.
• NOT for use with Aviation-type batteries

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 2 P/N VDC36271/48021-MNL
Glossary of Terms
• Maintain a battery
BatteryMINDer ensures batteries are truly fully charged and will likely
continue improving the condition of the battery to the fullest extent
possible.
• Rested
A battery that has been as fully charged as possible and left disconnected
from charger or any type load overnight.
• Specific Gravity
One of the key parameters of battery operation is the specific gravity of the
electrolyte. Specific gravity is the ratio of the weight of a solution to the
weight of an equal volume of water at a specified temperature. Specific
gravity is used as an indicator of the state of charge of a cell or battery.
• Sulfation
Occurs when the battery sits for long periods of time and the electrolyte
solution begins to break down. Sulfur in the solution leaches from the
electrolyte, sticking to the lead plates as converted lead sulfuric crystals.
Table Of Contents
Required Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Preparing to Charge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Charger Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
DC Connection Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Qualifying Your Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Testing a Filler Cap Lead-Acid Battery . . . . . . . . . . . . . . . . . . . . . . . 7
Specific Gravity – Capacity Table. . . . . . . . . . . . . . . . . . . . . . . . . . 9
Testing With a Hot/Cold Calibrated Hydrometer Tester . . . . . . . . . . . . . . . 9
Testing A Sealed, AGM or Flooded (Wet-Cell) Lead Acid Battery . . . . . . . . . . 9
Use a Digital Voltmeter Only . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
OCV/Full Capacity Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Unit Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Simplified Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . .12
Common Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Battery Condition Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
LED Status Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Detailed Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . .15
Multi-Battery Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Charge and Float Voltages at Various Temperature Ranges . . . . . . . . . . . . .19
Maintaining Multiple Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
For Repair or Replacement / Registration . . . . . . . . . . . . . . . . . . . . 23
Guarantee / Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 3 P/N VDC36271/48021-MNL
REQUIRED SAFETY INSTRUCTIONS
WARNING
READ AND FULLY UNDERSTAND BEFORE OPERATING
Contact VDC Electronics if uncertain about
any settings or operation.
TO REDUCE THE RISK OF FIRE, ELECTRIC SHOCK, OR
INJURY TO PERSON, OBSERVE THE FOLLOWING:
1. SAVE THESE INSTRUCTIONS
2. This manual contains important safety and operating instructions for
BatteryMINDer Models 36271 and 48021.
3. Do not expose charger to rain or snow.
4. Use of an attachment not recommended or sold by VDC Electronics
may result in a risk of fire, electric shock, or injury to persons.
5. To reduce risk of damage to electric plug and cord, pull by plug rather
than cord when disconnecting charger.
6. An extension cord should not be used unless absolutely necessary.
Use of improper extension cord could result in a risk of fire and electric
shock. If an extension cord must be used, make sure:
• That pins on plug of extension cord are the same number, size, and
shape as those of plug on charger;
• That extension cord is properly wired and in good electrical condition;
and
• That wire size is large enough for ac ampere rating of charger as
specified in Table below.
7. Do not operate charger with damaged cord or plug – replace the cord
or plug immediately.
8. Do not operate charger if it has received a sharp blow, been dropped,
or otherwise damaged in any way; call VDC Electronics Tech
Recommended minimum AWG size for
extension cords for battery chargers
AC input rating,
amperesa
AWG size of cord
Equal to
or
greater
than
But less
than
Length of cord, feet (m)
25
(7.6)
50
(15.2)
100
(30.5)
150
(45.6)
0 2 18 18 18 16
aIf the input rating of a charger is given in watts rather than in amperes, the
corresponding ampere rating is to be determined by dividing the wattage rating by
the voltage rating - for example: 1250 watts/125 volts = 10 amperes

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 4 P/N VDC36271/48021-MNL
Support Dept. 800.379.5579 x6 (ET) for advice.
9. Do not disassemble charger; call VDC Electronics Tech Support
Dept. 800.379.5579 x6 (ET) for advice when service or repair is
required. Incorrect reassembly may result in a risk of electric shock
or fire.
10. To reduce risk of electric shock, unplug charger from outlet before
attempting any maintenance or cleaning. Turning off controls will not
reduce this risk.
11. WARNING – RISK OF EXPLOSIVE GASES
a. WORKING IN VICINITY OF A LEAD-ACID BATTERY IS
DANGEROUS. BATTERIES GENERATE EXPLOSIVE GASES
DURING NORMAL BATTERY OPERATION. FOR THIS
REASON, IT IS OF UTMOST IMPORTANCE THAT YOU
FOLLOW THE INSTRUCTIONS EACH TIME YOU USE THE
CHARGER.
b. To reduce risk of battery explosion, follow these instructions and
those published by manufacturer of any equipment you intend to
use in vicinity of battery. Review cautionary marking on these
products and on engine.
12. PERSONAL PRECAUTIONS
a. Consider having someone close enough by to come to your aid
when you work near a lead-acid battery.
b. Have plenty of fresh water and soap nearby in case battery acid
contacts skin, clothing, or eyes.
c. Wear complete eye protection and clothing protection. Avoid
touching eyes while working near battery.
d. If battery acid contacts skin or clothing, wash immediately with
soap and water. If acid enters eye, immediately flood eye with
running cold water for at least 10 minutes and get medical
attention immediately.
e. NEVER smoke or allow a spark or flame in vicinity of battery or
engine.
f. Be extra cautious to reduce risk of dropping a metal tool onto
battery. It might spark or short-circuit battery or other electrical
part that may cause explosion.
g. Remove personal metal items such as rings, bracelets, necklaces,
and watches when working with a lead-acid battery. A lead-acid
battery can produce a short-circuit current high enough to weld a
ring or the like to metal, causing a severe burn.
h. Use charger for charging a LEAD-ACID battery only. It is not
intended to supply power to a low voltage electrical system other
than in a starter-motor application. Do not use battery charger

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 5 P/N VDC36271/48021-MNL
for charging dry-cell batteries that are commonly used with
home appliances. These batteries may burst and cause injury to
persons and damage to property.
i. NEVER charge a frozen battery or a battery at a temperature
above 123° F.
13. PREPARING TO CHARGE
a. If necessary to remove battery from vehicle to charge, always
remove grounded terminal from battery first. Make sure all
accessories in the vehicle are off, so as not to cause an arc.
b. Be sure area around battery is well ventilated while battery is
being charged.
c. Clean battery terminals. Be careful to keep corrosion from
coming in contact with eyes.
d. Add distilled water in each cell until battery acid reaches level
specified by battery manufacturer. Do not overfill. For a battery
without removable cell caps, such as valve regulated lead acid
batteries, carefully follow manufacturer’s recharging instructions.
e. Study all battery manufacturer’s specific precautions while
charging and recommended rates of charge.
f. Determine voltage of battery by referring to car owner’s manual
and make sure it matches output rating of battery charger.
14. CHARGER LOCATION
a. Locate charger as far away from battery as DC cables permit.
b. Never place charger directly above battery being charged; gases
from battery will corrode and damage charger.
c. Never allow battery acid to drip on charger when reading
electrolyte specific gravity or filling battery.
d. Do not operate charger in a closed-in area or restrict ventilation
in any way.
e. Do not set a battery on top of charger.
f. Always mount units in vertical position with cord sets exiting
downward to ensure weather tight integrity. Unit must be mounted
in this manner to ensure long term trouble free life including
weatherproof integrity. Mounting in any other manner or
using un-mounted (parallel to ground) except indoors may
cause unit to fail due to water intrusion that is unable to drain
correctly to avoid damage.
15. DC CONNECTION PRECAUTIONS
a. Connect and disconnect DC output clips only after setting any
charger switches to “off” position and removing ac cord from
electric outlet. Never allow clips to touch each other.
b. Attach clips to battery and chassis as indicated

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 6 P/N VDC36271/48021-MNL
in 15(e), 15(f), and 16(b) through 16(d).
16. FOLLOW THESE STEPS WHEN BATTERY IS
INSTALLED IN VEHICLE. A SPARK NEAR
BATTERY MAY CAUSE BATTERY EXPLOSION.
TO REDUCE RISK OF A SPARK NEAR BATTERY:
a. Position ac and DC cords to reduce risk of damage by hood, door,
or moving engine part.
b. Stay clear of fan blades, belts, pulleys, and other parts that can
cause injury to persons.
c. Check polarity of battery posts. POSITIVE (POS, P, +) battery
post usually has larger diameter than NEGATIVE (NEG, N,–)
post.
d. Determine which post of battery is grounded (connected) to the
chassis. If negative post is grounded to chassis (as in most
vehicles), see (e). If positive post is grounded to the chassis,
see (f).
e. When disconnecting charger, turn switches to off, disconnect AC
cord, remove clip from vehicle chassis, and then remove clip from
battery terminal.
f. See operating instructions for length of charge information.
17. FOLLOW THESE STEPS WHEN BATTERY IS OUTSIDE VEHICLE.
A SPARK NEAR THE BATTERY MAY CAUSE BATTERY
EXPLOSION. TO REDUCE RISK OF A SPARK NEAR BATTERY:
a. Check polarity of battery posts. POSITIVE (POS, P, +) battery
post usually has a larger diameter than NEGATIVE (NEG, N, –)
post.
b. Attach at least a 24-inch-long 6-gauge (AWG) insulated battery
cable to NEGATIVE (NEG, N, –) battery post.
c. Connect POSITIVE (RED) charger clip to POSITIVE (POS, P, +)
post of battery.
d. Position yourself and free end of cable as far away from battery
as possible – then connect NEGATIVE ( ) charger clip to
free end of cable.
e. Do not face battery when making final connection.
f. When disconnecting charger, always do so in reverse sequence
of connecting procedure and break first connection while as far
away from battery as practical.
g. A marine (boat) battery must be removed and charged on shore.
To charge it on board requires equipment specially designed for
marine use.

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 7 P/N VDC36271/48021-MNL
QUALIFYING YOUR BATTERY:
Preliminary Requirements
NOTE: The BatteryMINDer has no electrical output unless it is connected to
a healthy battery. Testing the BatteryMINDer with a volt or an Amp meter
without the unit being connected across a good battery will result in a false
reading. If you experience any problems, or are not sure of how to properly
use or connect your BatteryMINDer, please e-mail our technical support at:
[email protected] or call our toll-free technical support line
800-379-5579 x6 (Eastern Time). Be certain to leave your phone number
with the area code, time zone and the best time to call.
To gain the best result from your new charger and to maximize the life and
performance of your batteries we strongly recommend you qualify (test)
your batteries before attempting to either charge-maintain or desulfate them.
Remember, even if you just purchased a “new” battery it may have been
subjected to conditions that have caused “sulfation” such as high temperature
(>=80°).
NOTE: If your battery is new and you are certain it was not subject to
conditions that could have caused sulfation*, even before you purchased
it, then you can disregard our recommendations for qualifying / testing
your battery, before using the BatteryMINDer.
* Such as high temperature storage (=/> 80°F) and/or allowed to self-
discharge to 37.2 Volts / 49.6 Volts or lower.
Testing a Filler Cap or Manifold-type Lead Acid Battery
1. Carefully remove all caps from your battery.
2. Check the water-liquid electrolyte level. If the level is low or has ever
been below top of plates, severe lead plate sulfation has taken place.
Significant recharge/reconditioning time is needed to restore these plates
to a condition where the battery can be expected to function normally.
3. Refill each cell with distilled water only to the liquid level indicator found in
each cell. Before proceeding further you must be thoroughly familiar
with the safety and operating instructions.
4. Recharge the battery with the BatteryMINDer to ensure that it is slowly
and completely charged before you determine its condition. Allow battery
to “rest” (see Glossary of Terms) overnight for a minimum of 12 hours
before testing with a temperature compensated hydrometer and/or digital
type voltmeter only.

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 8 P/N VDC36271/48021-MNL
Specic Gravity – Capacity
Temperature Compensated
Hydrometer - Meter or 4 ball type
Full Capacity
Percentage
1.270 (4 Balls oating) 100%
1.250 (3 Balls oating) 75%
1.190 (2 Balls oating) 50%
1.150 (1 Balls oating) 25%
1.120 (0 Balls oating)
May denote shorted cell or battery that has
been severely discharged and may not be
recoverable
0%

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 9 P/N VDC36271/48021-MNL
Testing with a Hot/Cold Calibrated Hydrometer Tester
Read the tester instructions carefully for most accurate readings.
1. When using the tester the first time or after a long period of non-use, fill
the tester with the battery fluid and let it sit for 1/2 hour or longer. This will
soak the balls in order to give you more accurate readings. Failure to do
so will give you false readings indicating a battery that may not be in as
good a condition as you may have thought.
2. After inserting the tester in a cell, gently tap the tester several times
against the inside wall of each cell to dislodge air bubbles that will cause
more balls to float than should. Failure to do so will yield false readings
that indicate a battery that is not fully desulfated or does not qualify for
desulfation.
3. If no balls float in any cell, the cell is shorted. This means your battery is
beyond the point of being properly recharged or reconditioned-desulfated.
Dispose of the battery.
4. If each cell floats three (3) or more balls (or 1250 on gauge-type), your
battery can be desulfated-reconditioned.
5. Always rinse the tester with fresh water after every use. Failure to do so
will cause false readings.
Testing a Sealed, AGM or GEL Lead Acid Battery
These batteries have no filler caps or manifold-type covers. Because you
cannot gain access to the interior of your battery you cannot test it with a
hydrometer.
USE A DIGITAL VOLTMETER ONLY:
1. Recharge the battery with the BatteryMINDer to ensure it is as completely
charged as possible, before you determine its condition. Allow battery
to “rest” (see Glossary of Terms)overnight for a minimum of 12 hours
before testing with a digital voltmeter only. Failure to test a “rested”
battery will cause false readings. Be certain to read and understand all
safety related instructions (pages 3 to 6) before proceeding further.
2. Measure battery’s voltage, without any load attached. If the voltage is
less than 37.2 volts / 49.6 volts (Typically 50% of charge) the battery
may be too heavily sulfated to be fully recoverable. If voltage is 37.2V
/ 49.6V or higher full recovery can be expected, given sufficient time
(average 1-2 weeks for batteries that are heavily sulfated).

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 10 P/N VDC36271/48021-MNL
3. Connect the BatteryMINDer to the battery.
4. Charge battery to its maximum level. Allow battery to remain for a
minimum of 72 hours before retesting. If improvement is seen, continue
until battery voltage reaches full capacity level or no further increase is
seen.
Note: OPTIMA brand “Yellow Top” starter/deep cycle batteries have a
fully charged “resting” voltage of 39.3 / 52.4 (OCV). Increase above
values accordingly.
OCV=Open Circuit No Load Voltage
OCV - “Rested” Voltage Full Capacity
Percentage
36V 48V
38.7 - 39.3 51.6 - 52.4 Volts 100%
37.8 - 38.7 50.4 - 51.6 Volts 75%
37.2 - 37.8 49.6 - 50.4 Volts 50%
36.6 - 37.2 48.8 - 49.6 Volts 25%
36.0 - 36.6 48.0 - 48.8 Volts 0%
<33 Volts = shorted <44 Volts = shorted

BatteryMINDer® Models 36271 & 48021
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BatteryMINDer® Models 36271 & 48021
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SIMPLIFIED OPERATING INSTRUCTIONS
Read and thoroughly understand ALL SAFETY Instructions, pages
3 - 10 including Preparing to Charge, DC Connection Precautions,
Unit Location and Qualifying Your Battery BEFORE proceeding
further.
1. Attach a battery connector assembly, Ring Terminal Assembly (7)
(supplied) or EZC-01 EZ Connector (8), to output cordset of charger
(3) - see Detailed Operating Instruction on page 15 for information
on the EZC-01.
2. Attach output to battery terminals:
RED band = Positive +
BLACK band = Negative -.
3. Ambient Temperature Sensor, ATS-1 (9), comes already installed on
the Temperature Sensor input connector (2). Do not detach.
4. Plug AC power cord (5) into a 120 Vac electrical outlet.
Observe Reversed Polarity GREEN/RED LED indicator (1a):
If lit RED, reverse battery connector attachments on battery.
5. Observe Charging/Maintaining GREEN LED indicator (1c):
Solid = charging
Blinking = maintaining battery(s).
Charger will automatically start within 30 seconds or less.
6. Observe Battery Connected - Error LED Indicator (1a):
Must be lit GREEN1.
If in Doubt Regarding Any of the Above, Refer to Detailed Operating
Instructions.
1See full instructions if not lit GREEN.

BatteryMINDer® Models 36271 & 48021
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Common Features (Both Models)
1LED indicators (a, b & c) for power, connection, fault, battery, charge status
2Temperature Sensor input connector
3Output cord with quick connect plug
4Battery Type selection button
5Input power cordset
6Mounting tabs
7Ring Terminal cordset with quick connect plug (included)
8EZC-01 EZ Connector with screws (included)
9ATS-1 Ambient Temperature Sensor (included, shown installed on 2)
7
1
6
3
5
6
a
c
b
2
9
4
8

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LED INDICATOR FUNCTIONS
Battery Condition Table
Battery Condition Battery Voltage (Vb) Battery Condition Indication
36271 48021
BEFORE full charge <33 <44
>33 >44
Stop/Restart during charging
mode REBOOT to restart*
AFTER full charge Low Voltage
Normal Voltage
*To REBOOT: Disconnect A.C. wall power, disconnect D.C. Battery power and wait 10 seconds
LED Status Table
LED Status
(Power/Error and Charging/Maintaing LEDs)
POWER
ERROR CHARGE - FLOAT
A.C. power disconnected, battery connected
correctly OFF OFF
At SoftStart mode, Bulk charge mode or Absorption
mode ON ON
Float charge mode ON FLASHING
A.C. power connected Reversed Battery Polarity ON OFF
A.C. power connected, charger output clip shorted ON OFF
A.C. power connected, battery voltage <9V (36271)
or <12V (48021) ON OFF
Timed-out when in SoftStart or Bulk mode FLASHING OFF
Timed-out when in Absorption mode & Forced to
Float mode FLASHING FLASHING
Battery Fault / Battery Weak FLASHING OFF

BatteryMINDer® Models 36271 & 48021
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Detailed Operation Instructions for Models 36271 and 48021
After carefully reading and understanding the Safety Instructions contained
in this manual (pages 3 - 6) and having evaluated your battery as described
in Qualifying Your Battery (pages 7 - 10) you are properly prepared to begin
using your charger.
1. AttachoutputcordofchargertotheRingTerminalAssembly(RTA)(supplied).
Note: An optional method of connecting the BatteryMINDer to the RTA
is with the EZC-01 panel mounted assembly (supplied). This connector
is mounted through the side of the battery box under the golf cart seat,
making it convenient to connect the BatteryMINDer without lifting the seat.
To install:
a. Drill a small pilot hole
b. Use a 7/8” or 1” hole saw (available at such stores as Home Depot)
to complete drilling the hole.
c. Insert the EZC-01 into the hole and mark the four locations to drill the
pilot holes for the screws (supplied).
d. Install the screws
e. Connect the EZC-01 to the Ring Terminal Assembly.
Note the BatteryMINDer cord must be removed by pulling on the
connector plug, not the cord. Any damage to the connectors or cord
will not be covered by the warranty.
2. Never use either of these assemblies on any other charger or for any
other purpose such as improvised “jumper cables”, etc.
3. Using the RTA on batteries remaining in their normal use location (in
same place they are regularly installed will normally prove the safest
and most convenient. If you have several applications you may wish to
purchase additional Ring Terminal Assemblies (RTA) available from your
dealer or VDC Electronics, Inc. directly.
4. Note: this assembly contains a 15 Amp automotive type fuse and is
replaceable should for any reason it were to blow. Never replace this
fuse with any type whose rating is higher than 15 Amps, as seriously
harmful results may occur.
5. Identify the positive and negative posts or connections on your battery,
usually clearly designated with the polarity markings of + (positive) and
– (negative). If you have previously installed the RTA referred to in 1.
above, you need only to press the connector plug of the charger’s output
cord into the mating plug of the RTA. Push firmly and do not leave any

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 16 P/N VDC36271/48021-MNL
space between them. Correct polarity and a good connection will be your
reward.
6. Determine the type of battery you wish to charge. When certain
press the Select Battery Type button. The most common is the
Flooded kind, distinguished by removable filler caps (6) or two (2)
manifold covers (Maintenance-Free) which should not be removed
unless specifically allowed by the battery manufacturer. The second
most popular is the Absorbed Glass Mat (AGM) sealed-valve
regulated type. Lastly is the sealed valve regulated GEL battery.
Note: If unsure of your battery type, check with the battery seller,
manufacturer or our Tech Support before proceeding further. The normal
(default) setting of your charger is GEL, as this is the lowest voltage output
and thus the one least likely to cause your battery to be overcharged,
should you incorrectly select the wrong battery type. However be aware
that using the wrong setting for a particular type battery can dramatically
shorten its life and/or cause potentially explosive gas to be emitted from
the battery.
7. After selecting both battery type plug the unit’s power cord into a standard
– grounded 120 Vac electrical outlet. The Power ON LED Indicator will
light GREEN. If it does not light GREEN check the outlet to be sure it is
functioning. In addition, be sure if outlet is controlled by a switch, no one
will accidentally shut off the power to the outlet. Check for correct polarity
= (no ERROR RED LED Indicator). If ERROR Indicator is lit, reverse the
charger’s output connections to the battery.
8. The Charge – Float LED Indicator will light GREEN. The charger will
now begin charging by first checking the battery to determine its voltage
and ability to accept a charge. Should the battery not have a normal fully
discharged voltage (31.5V [36271] / 42.0V [48021] minimum) the unit will
begin charging in the “Soft-Start” mode to determine if the battery can
be safely charged. If it cannot, the Power ON – Error LED will flash RED
and charging will be stopped. Battery should be carefully checked under
a load by a qualified person before further attempting to charge it.
9. Note: If the battery does not have a minimum no load OCV (Open
Circuit Voltage) of 36 Volts / 48 Volts, the ERROR LED will light RED
and charger will reject battery.
10. No further effort should be made to charge this battery with this charger
or any charger. Discard this battery, unless it has just been subjected to a
long period of continuous discharge under a load such as can occur with

BatteryMINDer® Models 36271 & 48021
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leaving lights on or cranking an engine excessively. Allow such a battery
to “Rest” for several hours (overnight if possible) before determining if it
is defective. Be very suspicious of any 36V / 48V battery that does not
have at least 33V / 44 Volts (OCV) before it is recharged. It may well be
seriously damaged and unsafe for any type of use or recharge. The unit’s
Battery Condition Indication LED will help you determine if battery is less
than 33 Volts / 44 Volts (YELLOW) or greater than 33 Volts / 44 Volts
(GREEN)
11. After battery has been fully charged, the GREEN Charge-Float LED
Indicator will begin blinking. It will continue to blink indefinitely, unless
unit is disconnected from battery. Should battery be unable to be fully
charged, the LED will not blink and the RED Error LED will blink. Battery
may not be able to be fully charged, may be too large or too deeply
discharged to be fully charged in the normal time allowed by charger.
If you are certain battery is not defective, having read and understood
completely all of the above concerns and conditions, proceed to reboot
unit by unplugging from A.C. electrical outlet, disconnect from battery so
there will be no electrical power going to the unit from either direction,
wait 10 seconds, connect to battery only. Make battery selection if
needed by pushing SELECT BATTERY TYPE button once or twice,
then plug into A.C. outlet. This allows charger to begin charging battery
again. If battery is not defective it should be able to be fully charged after
being restarted. After sufficient time has lapsed the GREEN charge LED
Indicator will blink confirming when / if battery is now fully charged.
12. After carefully reading these instructions and Troubleshooting (pgs. 21 -
22) sections, should you still have questions, please e-mail our technical
support department at: [email protected].
13. Allow up to 3 business days for a detailed response to your questions.
Always identify the model number of the product and revision letter of this
manual contained on this page below. Without this information we may
not be able to assist you correctly.

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 18 P/N VDC36271/48021-MNL
12
V
+
_
12V
+
_
12V
+
_
+
_
6V
+
_
6V
+
_
6V
+
_
+
+
_
+
_
+
_
6V
6V
6
V
_
8V
+
–
8V
+
–
8V
+
–
8V
+
–
8V
+
–
8V
+
–
TO CHARGER +
TO CHARGER –
8 VOLT SERIES
6V
+
–
6V
+
–
6V
+
–
6V
+
–
6V
+
–
6V
+
–
6V
+
–
6V
+
–
TO CHARGER +
TO CHARGER –
6 VOLT SERIES
36 Volt
48 Volt
Battery Configurations
12V
+
–
12V
+
–
12V
+
–
12V
+
–
12 VOLT SERIES
TO CHARGER +TO CHARGER –

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 19 P/N VDC36271/48021-MNL
The chart below shows the need to regulate the output voltage of the charger
to ensure against over or under charging your battery over a wide range of
temperatures.
Temperature Compensated Flooded Battery*
Charge and Float Voltages
36V 48V
Temperature Charge Float Charge Float
> 120°F 41.4 38.4 55.2 V 51.2 V
110°F - 120°F 41.7 38.7 55.6 V 51.6 V
100°F - 110°F 42.0 39.0 56.0 V 52.0 V
90°F - 100°F 42.3 39.3 56.4 V 52.4 V
80°F - 90°F 42.9 39.9 57.2 V 53.2 V
70°F - 80°F 43.2 40.2 57.6 V 53.6 V
60°F - 70°F 43.8 40.8 58.4 V 54.4 V
50°F - 60°F 44.4 41.4 59.2 V 55.2 V
40°F - 50°F 45.0 42.0 60.0 V 56.0 V
< 40°F 45.3 42.3 60.4 V 56.4 V
*AGM Charge & Float: +0.6 V (36271) / +0.8 V (48021)
Gel Charge & Float: -0.6 V (36271) / -0.8 V (48021)

BatteryMINDer® Models 36271 & 48021
Rev. D-120913 Page 20 P/N VDC36271/48021-MNL
MAINTAINING MULTIPLE BATTERIES
BatteryMINDer 36271 or 48021 Battery Maintainer-Desulfators can be used
to maintain up to eight batteries at a time, providing each battery is fully
operational (no dead-dying cells), free of sulfate and meeting the minimum
full charge “rested” (see Glossary of Terms)voltage of 2.13 volts / cell,
after being fully desulfated.
ALL batteries Must be properly tested to ensure they are in good condition
(no dead-dying cells or excessive sulfation) before maintaining them
in multiples. Only healthy, fully desulfated batteries should ever be
MAINTAINED in sets of 2 or more. Test each cell of All filler cap batteries
using an accurate, temperature compensated hydrometer.
Test sealed (no filler caps) batteries using an accurate, DIGITAL type ONLY,
voltmeter. The Minimum voltage Must not be less than 2.13 volts / cell
after fully charging battery and letting it “rest” for 12 hours minimum, before
testing. If battery voltage is less than 2.13 / cell you must first desulfate it
until you reach a “rested” voltage of 2.13 volts / cell.
Attempting to desulfate more than one (1) battery at a time will yield very
poor results, as the strongest (healthiest) and not the weakest (most
sulfated) battery will receive the majority of the desulfation pulse energy.
Exception is when batteries are identical and have been used in parallel or
series with each other during their entire life.