MASTERVOLT MLI Ultra 1250 12V/100Ah Lithium Pack, ChargeMaster PLUS CZone Charger / 24 V / 20 A / 3 charging outputs, ChargeMaster PLUS CZone Charger / 12 V / 35 A / 3 charging outputs, ChargeMaster PLUS CZone Charger / 24 V / 30 A, ChargeMaster PLUS CZone Charger / 12 V / 50 A / 3 charging outputs Manual

CHARGEMASTER PLUS

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3

AUTOMATIC BATTERY CHARGER

USER AND INSTALLATION MANUAL

10000016594/03

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2

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

TABLE OF CONTENTS

1 GENERAL INFORMATION ......................... 3

1.1 Use of this manual .................................... 3

1.2 Liability ....................................................... 3

1.3 Warranty .................................................... 3

1.4 Disclaimer .................................................. 3

1.5 Identification label .................................... 3

1.6 Correct disposal of this product ............. 3

2 SAFETY INSTRUCTIONS ........................... 4

2.1 General ...................................................... 4

2.2 Explosive gases ........................................ 4

2.3 Personal precautions ............................... 5

2.4 Warnings regarding the use of batteries 5

2.5 Charger location ....................................... 5

2.6 DC connection precautions .................... 5

2.7 When battery is installed in vehicle ....... 6

2.8 When battery is outside vehicle ............. 6

2.9 Preparing to charge ................................. 6

2.10 Grounding instructions ............................ 7

2.11 Warning regarding life support

applications ............................................... 7

3 INSTALLATION .......................................... 8

3.1 Unpacking ................................................. 8

3.2 Location ..................................................... 8

3.3 Wiring ......................................................... 8

3.3.1 DC wiring ......................................... 8

3.3.2 AC wiring ......................................... 9

3.3.3 AC safety grounding ...................... 9

3.3.4 Network wiring

(CZone/MasterBus) ................................ 10

3.4 Batteries ................................................... 10

3.5 Things you need ..................................... 10

3.6 Overview of the connection

compartment ........................................... 11

3.7 Connection example .............................. 12

3.8 Installation step-by-step ......................... 13

3.9 Commissioning after installation .......... 15

4 SETTINGS ................................................. 16

4.1 DIP switch settings ................................. 16

4.2 MasterBus configuration ....................... 16

4.2.1 Monitoring ..................................... 17

4.2.2 Alarms ............................................ 17

4.2.3 History ............................................ 18

4.2.4 Configuration settings.................. 18

4.2.5 Events – System automation ...... 19

4.2.6 Current control ............................. 20

4.3 MasterShunt ............................................ 21

4.4 Lithium-ion Battery MLI Ultra ................ 21

4.5 CZone configuration .............................. 21

5 OPERATING INSTRUCTIONS .................. 22

5.1 Introduction ............................................. 22

5.2 Switching on / off .................................... 22

5.3 Status display .......................................... 22

5.4 The 3-step+ charge process ................. 23

5.4.1 Charge voltages ........................... 24

5.4.2 Pre-float ......................................... 24

5.4.3 Temperature compensated

charging ................................................... 24

5.4.4 Flat battery support ...................... 24

5.5 DC OUT ................................................... 24

5.6 Maintenance ............................................ 24

5.7 Storage .................................................... 25

6 TROUBLE SHOOTING .............................. 26

7 TECHNICAL DATA ................................... 28

7.1 Specifications 12V models .................... 28

7.2 Specifications 24V models .................... 29

7.3 Dimensions .............................................. 30

7.4 Characteristics ........................................ 30

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

3

1 GENERAL INFORMATION

1.1 Use of this manual

This manual serves as a guideline for the safe
and effective operation and maintenance of the
following ChargeMaster Plus models:

Part number

Model

44310355

12/35-3

44310505

12/50-3

44320205

24/20-3

44320305

24/30-3

These models are further referred to as
“ChargeMaster Plus”.

1.2 Liability

Mastervolt can accept no liability for:

• Consequential damage resulting from the use

of the ChargeMaster Plus.

• Possible errors in the included manual and

the consequences of these.

• Use that is inconsistent with the purpose of

the product.

1.3 Warranty

The Mastervolt product warranty covers the
ChargeMaster Plus for the first two years after
the purchase date, on the condition that the
product is installed and used according to the
instructions in this manual.

Installation or use that do not comply with these
instructions may result in under performance,
damage or failure of the product and may void
this warranty. The warranty is limited to the cost
of repair and/or replacement of the product.
Costs of labor or shipping are not covered by this
warranty.

1.4 Disclaimer

Our products are subject to continual
development and improvement. Therefore,
additions or modifications to the products may
cause changes to the technical data and
functional specifications. No rights can be
derived from this document. Please consult our
most current Terms & Conditions of Sale.

1.5 Identification label

The following picture is only an example!

Part number Serial number.

Figure 1: Identification label

The identification label is located at the right­hand side of the ChargeMaster Plus. Important
technical information required for service,
maintenance & secondary delivery of parts can
be derived from the identification label.

CAUTION!

Never remove the identification
label. This will void the warranty.

1.6 Correct disposal of this product

This product is designed and
manufactured with high quality
materials and components,
which can be recycled and
reused.

Please be informed about the local separate
collection system for electrical and electronic
products.

Please act according to your local rules and do
not dispose of your old products with your
normal household waste. The correct disposal of
your old product will help prevent potential
negative consequences to the environment and
human health.

4

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

2 SAFETY INSTRUCTIONS

IMPORTANT SAFETY INSTRUCTIONS

SAVE THESE INSTRUCTIONS

WARNING!

Read the entire manual before
using the ChargeMaster Plus.
Keep this manual in a secure
place.

This chapter describes important safety and
operating instructions for use of a ChargeMaster
Plus in residential, recreational vehicle (RV) and
marine applications.

2.1 General

1 The appliance is not to be used by children or

persons with reduced physical, sensory or
mental capabilities, or lack of experience and
knowledge, unless they have been given
supervision or instruction.

2 This appliance can be used by children aged

from 8 years and above and persons with
reduced physical, sensory or mental capa­bilities or lack of experience and knowledge,
if they have been given supervision or instruc­tion concerning use of the appliance in a safe
way and understand the hazards involved.

3 Children shall not play with the appliance.
4 Cleaning and user maintenance shall not be

made by children without supervision.

5 To reduce the risk of electric shock – Do not

expose the ChargeMaster Plus to rain, snow,
spray, moisture, excessive pollution and
condensing circumstances. To reduce risk of
fire hazard, do not cover or obstruct the
ventilation openings. Do not install the
ChargeMaster Plus in a non-ventilated room,
as overheating may result.

6 Use of an attachment or spare part not

recommended or sold by Mastervolt may
result in a risk of fire, electric shock, or
personal injury.

7 UL 1236 requirements do not cover investiga-

tion of charging Lithium-ion type batteries.

8 The ChargeMaster Plus is designed to be

permanently connected to an AC and DC
electrical system. Installation of, and work on
the ChargeMaster Plus, may be carried out
only by qualified and trained personnel,

consistent with the locally applicable
standards and regulations.

9 Make sure that all wiring is properly installed,

in good electrical condition, and correctly
sized to match the AC ampere rating of the
ChargeMaster Plus. Check the wiring on a
regular base, at least once a year. Do not use
the ChargeMaster Plus when the wiring is
undersized or damaged.

10 Do not operate the ChargeMaster Plus if it has

received a sharp blow, been dropped, or
otherwise damaged in any way; take it to a
qualified serviceman.

11 Except for the connection compartment, see

chapter 3, the ChargeMaster Plus may not be
opened or disassembled. There are no
serviceable parts inside the cabinet. Take it to
a qualified, authorized and trained serviceman
when service or repair is required. Incorrect
reassembly may result in a risk of electric
shock or fire.

12 To reduce risk of electric shock, disconnect

the ChargeMaster Plus from both AC and DC
electrical system before attempting any
maintenance or cleaning. Turning off controls
will not reduce this risk. Be sure that third
parties cannot reverse the measures taken.

13 The ChargeMaster Plus must be provided

with an equipment-grounding conductor to
the AC input ground terminal. Grounding and
all other wiring must comply with local codes
and ordinances.

14 Short circuiting or reversing polarity will lead

to serious damage to batteries, ChargeMaster
Plus, wiring as well as accessories. Fuses
cannot prevent damage caused by reversed
polarity and the warranty will be void.

15 In case of fire, you must use the fire extin-

guisher which is appropriate for electrical
equipment.

16 If applied in a marine application in the United

States, external connections to the
ChargeMaster Plus shall comply with the
United States Coast Guard Electrical
Regulations (33CFR183, Sub part I).

2.2 Explosive gases

1 WARNING – RISK OF EXPLOSIVE

GASES. WORKING IN VICINITY OF A
LEAD-ACID BATTERY IS DANGEROUS.

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

5

BATTERIES GENERATE EXPLOSIVE
GASES DURING NORMAL BATTERY
OPERATION. FOR THIS REASON, IT IS
OF UTMOST IMPORTANCE THAT EACH
TIME BEFORE USING THE ChargeMaster
Plus, YOU READ THIS MANUAL AND
FOLLOW THE INSTRUCTIONS
EXACTLY.

2 To reduce risk of battery explosion, follow

these instructions and those published by
battery manufacturer and manufacturer of
any equipment you intend to use in vicinity of
the battery. Review cautionary marking on
these products and on engine.

3 DANGER: To reduce the risk of

explosion – Never use the ChargeMaster
Plus in situations where there is danger of
gas or dust explosion or area in which
ignition-protected equipment is required.

2.3 Personal precautions

1 Consider having someone close enough by to

come to your aid when you work near a lead­acid battery.

2 Have plenty of fresh water and soap nearby in

case battery acid contacts skin, clothing, or
eyes.

3 Wear eye and clothing protection. Avoid

touching eyes while working near battery.

4 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.

5 NEVER smoke or allow a spark or flame in

vicinity of battery or engine.

6 Be extra cautious to reduce risk of dropping a

metal tool onto battery. It might spark or short­circuit battery or other electrical part that may
cause explosion.

7 Do not wear watches, bracelets, necklaces or

other metal objects when working on
batteries.

2.4 Warnings regarding the use of

batteries

1 Only use the ChargeMaster Plus for charging

Lead-Acid or lithium-ion batteries and the

supply of consumers attached to these
batteries, in permanent systems. Do not use
the ChargeMaster Plus 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. Make sure lithium-ion batteries used
for this charger are certified to EN standards.

2 NEVER charge non-rechargeable batteries.
3 NEVER charge a frozen battery.
4 Excessive battery discharge and/or high

charging voltages can cause serious damage
to batteries. Do not exceed the recommended
limits of discharge level of your batteries.

5 If it is necessary to remove a battery, always

remove grounded terminal from battery first.
Make sure all accessories are off, so as not to
cause an arc.

6 Be sure that the area around battery is well

ventilated while battery is being charged.
Refer to the recommendations of the battery
manufacturer.

7 Batteries are heavy! It may become a

projectile if it is involved in an accident!
Ensure adequate and secure mounting and
always use suitable handling equipment for
transportation.

2.5 Charger location

1 Never place charger directly above battery

being charged; gases from battery will
corrode and damage charger.

2 Never allow battery acid to drip on charger

when reading electrolyte specific gravity or
filling battery.

3 Do not operate charger in a closed-in area or

restrict ventilation in any way.

4 Do not set a battery on top of charger.

2.6 DC connection precautions

1 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.

2 Attach clips to battery and chassis as

indicated in section 2.7, steps 5 and 6, and 2.8
steps 2 through 4.

6

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

2.7 When battery is installed in vehicle

A SPARK MAY CAUSE BATTERY EXPLOSION.

To reduce risk of a spark near battery:

1 Position AC and DC cords to reduce risk of

damage by hood, door, or moving engine
part.

2 Stay clear of fan blades, belts, pulleys, and

other parts that can cause injury to persons.

3 Check polarity of battery posts. POSITIVE

(POS, P, +) battery post usually has larger
diameter than NEGATIVE (NEG, N, –) post.

4 Determine which post of battery is grounded

(connected) to the chassis. If negative post is
grounded to chassis (as in most vehicles), see
(5). If positive post is grounded to the chassis,
see (6).

5 For negative-grounded vehicle, connect

POSITIVE (RED) clip from battery charger to
POSITIVE (POS, P, +) ungrounded post of
battery. Connect NEGATIVE (BLACK) clip to
vehicle chassis or engine block away from
battery. Do not connect clip to carburetor, fuel
lines, or sheet-metal body parts. Connect to a
heavy gage metal part of the frame or engine
block.

6 For positive-grounded vehicle, connect

NEGATIVE (BLACK) clip from battery charger
to NEGATIVE (NEG, N, –) ungrounded post of
battery. Connect POSITIVE (RED) clip to
vehicle chassis or engine block away from
battery. Do not connect clip to carburetor, fuel
lines, or sheet-metal body parts. Connect to a
heavy gage metal part of the frame or engine
block.

7 When disconnecting charger, turn switches to

off, disconnect AC cord, remove clip from
vehicle chassis, and then remove clip from
battery terminal.

8 See operating instructions for length of

charge information.

2.8 When battery is outside vehicle

A SPARK MAY CAUSE BATTERY EXPLOSION.

To reduce risk of a spark near battery:

1 Check polarity of battery posts. POSITIVE

(POS, P, +) battery post usually has a larger
diameter than NEGATIVE (NEG, N, –) post.

2 Attach at least a 24-inch-long 6-gauge (AWG)

insulated battery cable to NEGATIVE (NEG, N,
–) battery post.

3 Connect POSITIVE (RED) charger clip to

POSITIVE (POS, P, +) post of battery.

4 Position yourself and free end of cable as far

away from battery as possible – then connect
NEGATIVE (BLACK) charger clip to free end
of cable.

5 Do not face battery when making final

connection.

6 When disconnecting charger, always do so in

reverse sequence of connecting procedure
and break first connection while as far away
from battery as practical.

2.9 Preparing to charge

1 If it is 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.

2 Be sure area around battery is well ventilated

while battery is being charged.

3 Clean battery terminals. Be careful to keep

corrosion from coming in contact with eyes.

4 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.

5 Study all battery manufacturer’s specific

precautions while charging and
recommended rates of charge.
Note that the ChargeMaster Plus charge
specifications are based on Mastervolt
batteries. Specifications for a given chemistry
of a different manufacturer may vary. If
connecting batteries of a different
manufacturer, make sure the manufacturer's
recommendations are met.

6 Determine voltage of battery by referring to

car owner’s manual and make sure that
output voltage selector switch is set at correct
voltage. If charger has adjustable charge rate,
charge battery initially at lowest rate.
Exception: For a charger not having an output
voltage selector switch, determine voltage of

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

7

battery by referring to car owner’s manual and

make sure it matches output rating of battery
charger.

2.10 Grounding instructions

This battery charger should be connected to a
grounded, metal, permanent wiring system; or an
equipment-grounding conductor should be run
with circuit conductors and connected to
equipment-grounding terminal or lead on battery
charger. Connections to battery charger should
comply with all local codes and ordinances.

2.11 Warning regarding life support

applications

Mastervolt products are not designed to be used
as component of medical equipment, unless
negotiated in the form of a written agreement
between customer and/or manufacturer and
Mastervolt. Such agreement will require the
equipment manufacturer either to contract
additional reliability testing of the Mastervolt
parts and/or to commit to undertake such testing
as a part of the manufacturing process.
Furthermore, the manufacturer must agree to
indemnify and not hold Mastervolt responsible
for any claims arising from the use of the
Mastervolt parts in the life support equipment.

8

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

3 INSTALLATION

During installation and commissioning, the safety
instructions are applicable at all times.

3.1 Unpacking

In addition to the ChargeMaster Plus the delivery
includes:

• Mounting bracket to mount the ChargeMaster

Plus to a wall;

• Battery temperature sensor;

• Drop cable CZone/MB (1m);

• MasterBus Terminator;

• User and installation manual.

After unpacking, check the contents for possible
damage. Do not use the product if it is damaged.
If in doubt, contact your supplier

Check from the identification label (see section

1.5) whether the battery voltage is the same as
the nominal output voltage of the ChargeMaster
Plus (e.g. 24V battery set for a 24V battery
charger).

3.2 Location

• The ChargeMaster Plus is designed for indoor

use only.

• Ambient temperature: -25°C ... 80°C / -13°F …

176°F; (power derating above 40°C / 104°F to
decrease the internal heat sink temperature).

• Humidity: 0-95% non-condensing

• Mount the ChargeMaster Plus vertically, with

the connecting cables downwards.

• Do not expose the ChargeMaster Plus to

excessive dust, aggressive environments,
ammonia or salt.

• Make sure that the hot air that is developed

during operation can be discharged. The
ChargeMaster Plus must be mounted in such
a way that obstruction of the airflow through
the ventilation openings will be prevented.

• This device requires a minimum of 100mm

(4") of clearance on every side.

• If added to a CZone or MasterBus network,

take the network powering into consideration.

• Never place the ChargeMaster Plus directly

above the battery being charged, as gases
from battery will corrode and damage the
ChargeMaster Plus.

• If the ChargeMaster Plus is installed in the

immediate vicinity of living areas, take into
account that even though we took the highest
care, the fan of the ChargeMaster Plus can
produce noise when operating.

• Although the ChargeMaster Plus fully

complies with all applicable EMC limits, it may
still cause harmful interference to radio
communication equipment. If such interfe­rence appears, it is recommended to increase
the separation between the ChargeMaster
Plus and the equipment, to relocate the
receiving antenna or to connect the
equipment to a circuit different from that to
which the ChargeMaster Plus is connected.

3.3 Wiring

WARNING!

The wire sizes stated in this
manual are given as guideline
only. Always comply with all local
rules and regulations.

3.3.1 DC wiring

Keep in mind that high current will pass through
the DC wiring. Keep the cable length as short as
possible, this will keep the system efficiency as
high as possible. The recommended minimum
cross section of the battery cables is:

ChargeMaster
Plus model

DC Cable cross section:

<3m
10ft

3-5m/10­16ft

12/35-3

10 mm²
8 AWG

16 mm²
6 AWG

12/50-3

16 mm²
6 AWG

25 mm²
4 AWG

24/20-3

6 mm²
10 AWG

10 mm²
8 AWG

24/30-3

10 mm²
8 AWG

16 mm²
6 AWG

0

20

40

60

80

100

120

-50

-40

-30

-20

-10

0

102030405060708090

100

Output Power (%)

Temperature (°C)

Output Power vs Temperature

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

9

Use the following wire colors for DC wiring color
or at least different colors to make a clear
distinction between the positive and negative
wire from the battery:

Wire color

Meaning

Connect to:

Red

Positive

+ (POS)

Black

Negative

– (NEG)

Run the positive and negative cables next to
each other to limit the electromagnetic field
around the cables. The negative cable should be
connected directly to the negative post of the
battery bank or the ground side of a current
shunt. Do not use the chassis frame as the
negative conductor. Tighten securely. The
positive battery cable must be fused and
connected to the positive post of the battery
bank.

The recommended DC fuses for DC 1/2/3 OUT
are:

Model

DC fuse

Model

DC fuse

12/35-3

40 A

24/20-3

25 A

12/50-3

60 A

24/30-3

40 A

The fuse with the fuse-holder is available from
your local Mastervolt distributor or Customer
Service Representative.

3.3.2 AC wiring

WARNING!

On first connecting to power,
make sure the ChargeMaster
Plus is in a well-ventilated area as
it might spark.

For a safe installation the correct wire cross

section must be applied. Don’t use a cross

section that is smaller than indicated. See the
following table to select the appropriate cross
section for the AC wiring (up to 6m / 20ft length):

Wire size

Max. current

Solid wire (3x)

1.5 – 6 mm

2

14 – 10 AWG

15A

Stranded wire (3x)

1.5 – 6 mm

2

14 – 8 AWG

15A

Ferruled wire (3x)

1.5 – 4 mm

2

14 – 10 AWG

15A

Connection of AC wiring and recommended wire
colors:

• 240VAC, 50/60Hz installations:

Wire color

Meaning

Must be
connected to:

Brown or
black

Phase

L

Blue

Neutral

N

Green/Yellow

Earth

• 120VAC, 50/60Hz installations (single phase):

Wire
color

Meaning

Must be
connected to:

Black

Hot or Line

L

White

Neutral

N

Green

Ground

• 240VAC, 50/60Hz (split phase 120/240VAC):

Wire
color

Meaning

Must be
connected to:

Black (L1)

Hot or Line

L

Red (L2)

Hot or Line

N

Green

Ground

Note: An accessible disconnection device

(switch or circuit breaker for example)
must be incorporated in the AC wiring, in
accordance with wiring rules.

3.3.3 AC safety grounding

WARNING!

The ground wire offers protection
only if the enclosure of the
ChargeMaster Plus is connected
to the safety ground. Connect the
ground terminal (PE / GND) to the
hull, chassis or Distribution
Apparatus.

CAUTION!

According to local regulations an
RCD/Breaker (also known as
GFCI) must be placed in the AC
input circuit of the ChargeMaster
Plus.

For Australia and New Zealand, the
wiring rules are in accordance with
AS/NZS 3000.

10

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

3.3.4 Network wiring (CZone/MasterBus)

The ChargeMaster Plus can be connected to a
CZone or MasterBus network. Use an RJ45 Drop
cable CZone/MB or MasterBus cable and daisy
chain the ChargeMaster Plus to the other
devices, forming a local data network. Both
networks need a terminating device on both
ends of the network. Do not make ring networks
or T-connections.

• CZone network

Points to consider:

˗ Up to 40 devices can be connected together

on a single backbone.

˗ Make sure the CZone network has two

terminating resistors, one at each open end
of the backbone.

˗ The electric power for the network comes

from a battery or power supply. Make sure
that it delivers enough power and is
positioned as close to the middle of the
backbone as possible to reduce voltage
drop.

• MasterBus network

Points to consider:

˗ Connections between the devices are made

by standard MasterBus cables (straight
UTP). Mastervolt can supply these cables.

˗ Up to 63 MasterBus devices can be

connected together.

˗ The electric power for the network comes

from the connected devices according to the
rule: 1powering / 3 non-powering. Spread
the powering devices over the network.

For more details on networks, please contact
your Mastervolt supplier.

3.4 Batteries

Always follow the instructions published by the
battery manufacturer.

Model

Minimum

battery

capacity

MVG

(Mastervolt Gel

battery)

12/35-3

70 Ah

85

12/50-3

100 Ah

120

24/20-3

40 Ah

55

24/30-3

60 Ah

85

3.5 Things you need

Make sure you have all the parts you need to
install the ChargeMaster Plus:

• ChargeMaster Plus (included).

• Battery temperature sensor with cable and

plug (included).

• DC cables to connect the ChargeMaster Plus

to the batteries and common negative; see
section 3.3.1 for specifications.

• DC fuse holder with a DC fuse, to be

integrated in the positive DC cable; see
section 3.3.1 for specifications.

• Screws/bolts (Ø 6mm with plugs) to mount

the ChargeMaster Plus to a surface. Use
mounting materials which are suitable to carry
the weight of the ChargeMaster Plus.

• AC cable to connect the AC input to an AC

power source. See section 3.3.2.

• Batteries. See section 3.4.

• Appropriate and reliable cable terminals,

cable lugs, battery terminals and cord end
terminals.

• For CZone setup, an RJ45-M12 Drop cable

CZone/MB (included) and a tee connector
(not included). When connecting several
drop cables in a similar location, use a 2-way
or 4-way tee connector

• For MasterBus setup, an RJ45 MasterBus

cable (not included).

We recommend as a minimum tool kit:

• Socket wrench 10mm to fix the main DC

cables.

• Socket wrench 10mm to fix the Safety ground

connection.

• Flat blade screwdriver 1.0 × 4.0mm to fix the

screw terminals of the AC wiring.

• Tools to fix the screws / bolts (Ø 6mm) with

plugs to mount the ChargeMaster Plus to a
surface.

• Philips screwdriver number 2 to open the

connection compartment.

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

11

3.6 Overview of the connection compartment

1. Spring cage terminal AC input

2. Strain relief for AC wiring

3. Safety ground connection 1*

4. Safety ground connection 2*

5. Positive terminal charge output 1;

DC 1 OUT

6. Positive terminal charge output 2;

DC 2 OUT

7. Positive terminal charge output 3;

DC 3 OUT

8. Common negative output terminal

9. DIP switches

10. Network connection

(CZone/MasterBus)

11. Temperature sensor connection

Figure 2: Connections

* There are two safety ground connections. Use only one of them. For details see section 3.7 Connection

example.

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3.7 Connection example

This schematic illustrates the general placement of the ChargeMaster Plus in a circuit. It is not meant to
provide detailed wiring instructions for any particular electrical installation.

Figure 3: Installation drawing of the ChargeMaster Plus

* Use only one of the two options.

When installing the AC wires, keep extra length available for the PE, ensuring the PE will be the last
wire to get taut if the wire slips through the anchorage.

Notes:

- If the battery temperature remains within 15-25°C (59-77°F), connection of the battery temperature

sensor is optional.

- Lithium-ion batteries require no temperature sensor.

- If creating a parallel system of multiple ChargeMaster Plus units, the units should be excluded from any

isolation measurement system.

CZone/MasterBus

Network

RCD/Breaker

L1

N/L2

PE/GND* option 1

PE/GND* option 2

Battery

fuse

Battery

fuse

Battery

fuse

BATTERY BANK 1

(main battery bank)

BATTERY

BANK 3

BATTERY

BANK 2

Temperature sensor

OPTIONAL

COMMON NEGATIVE (–)

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13

WARNING!

All electrical systems (AC and DC)
must be disconnected from any
power source during the entire
installation!

CAUTION!

Too-thin cables and/or loose
connections can cause dangerous
overheating of the cables and/or
terminals. Therefore, tighten all
connections well, in order to limit
transition resistance as far as
possible. Use cables of the correct
size.

CAUTION!

Short circuiting or reversing polarity
may lead to serious damage to the
batteries, the ChargeMaster Plus, the
cabling and/or the terminal
connections. Fuses between the
batteries and the ChargeMaster Plus
cannot prevent damage caused by
reversed polarity. The damage as a
result of reverse polarity is
detectable by the service depart­ment and is not covered by the
warranty.

3.8 Installation step-by-step

1

2

3

Open the connection
compartment by loosening the two

screws.

4

Fix the enclosure to the wall by
fastening two screws at the lower side

of the ChargeMaster Plus as well.

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5

Connect the AC wiring to the screw

terminals. Fasten the cable with the
strain relief.

6

Integrate a fuse holder in the positive
battery wire but do not place the fuse

yet!
Fit crimp-on cable lugs to the DC

cables. Connect the DC cabling of

battery bank 1, positive to +, negative

to – .

Repeat steps for output 2 and 3.

7

Attach the battery temperature sensor

to the casing of battery bank 1.
Plug the temperature sensor cable

into the “Temp sense” jack.

Option: Connect the ChargeMaster to

the CZone or MasterBus network.

8

Adding to a CZone network

1 Disconnect the backbone at the

closest backbone connection and
add in a tee connector.

2 Reconnect the backbone

connection(s) with the new tee
connector in place.

3 Connect the RJ45 CZone/MB drop

cable to the black coupler on the tee
and then connect to the
ChargeMaster Plus.

Adding to a MasterBus network

1 Disconnect a MasterBus cable or

Terminator from the closest

MasterBus device and connect it to
the ChargeMaster Plus.

2 Connect the new MasterBus cable to

the other MasterBus device and then
connect to the ChargeMaster Plus.

Ensure that the network is properly
terminated.

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15

3.9 Commissioning after installation

1 Check the wiring; positive connected to

positive (red cables), negative connected to
negative (black cables).

2 When all wiring is OK, place the DC fuse(s) to

connect the batteries to the ChargeMaster
Plus.

WARNING!

When placing this fuse, a spark
might occur, caused by the
capacitors used in the
ChargeMaster Plus. This is
particularly dangerous in
places with insufficient
ventilation. Due to the gassing
of the batteries, an explosion
can occur. Avoid having
flammable materials close by.

3 Switch on the AC power supply.

Note: when new, the ChargeMaster Plus will

not start charging batteries before activated
with the ON/OFF button. See step 6.

4 Check the DIP switches.

See chapter DIP switch settings on page 16.

5 Check and adjust the settings of the

ChargeMaster Plus with MasterAdjust
(MasterBus network) or with the CZone
Configuration Tool (CZone network).
See chapter SETTINGS on page 16.

6 When the settings meet the power system's

needs, press and hold the ON/OFF button for
3 seconds to switch the charger on and
initiate the charging process.

9

If required, use a small screwdriver to
change DIP switch settings. See

section 4.1.

10

Check all wiring; see also Figure 3

for wiring details. If all wiring is OK:

Place the DC fuses.

11

Close the connection compartment
by fixing the screws.

12

Continue with section 3.9 for

commissioning of the ChargeMaster

Plus.

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ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

4 SETTINGS

Adjustment of the settings of the ChargeMaster
Plus can be made in two different ways:

• By means of DIP switches.

• From a laptop or notebook connected to the

ChargeMaster Plus via a USB Interface. Some
settings can only be changed in this way.

CAUTION!

Invalid settings of the
ChargeMaster Plus can cause
serious damage to your batteries
and/or the connected load! Only
authorized personnel may adjust
settings.

When required, the ChargeMaster Plus can be
restored to factory settings (see section 4.2).

4.1 DIP switch settings

Use a small screwdriver to carefully set the
required settings.

Figure 4: DIP switches (factory settings)

DIP switch 1 = CZone (0) or MasterBus (1)
network.

DIP switch 2 = MasterBus powering off (0) or
on (1)

DIP switches 3 to 10 are either used as CZone
address or for MasterBus battery settings.

In a CZone network:
DIP switch 1 must always be set to the OFF

position (0).
DIP switch 2 must always be set to the OFF

position (0).
DIP switches 3 to 10 must match the unique

address used in the CZone network; the
dipswitch. See the CZone Configuration Tool
Instructions manual for more information.

In a MasterBus network:

DIP switch 1 must always be set to the ON
position (1).

DIP switch 2 is MasterBus Powering ON (1) or OFF
(0).

DIP switches 3 to 5 are used for battery type
selection:

DIP switch

3 4 5

MasterBus settings (Flooded)1

0 0 0

Flooded (fixed)

0 0 1

AGM (fixed)

0 1 0

Gel (fixed)

0 1 1

Lithium-ion (fixed)

1 0 0

Constant voltage (13,25/26,50V)2

1 1 1

1

If all DIP switches are in the OFF position (0 ), the

settings suit a Flooded battery but can be changed
in MasterAdjust.

2

Constant voltage has no temperature compensation

See section 5.4 for more information on charge
voltage settings and section 5.5 for DC OUT.

4.2 MasterBus configuration

MasterBus is a CAN based data network for communication between Mastervolt devices. When the
ChargeMaster Plus is connected, open MasterAdjust on a Windows laptop or notebook connected to the
MasterBus network via a MasterBus USB interface. MasterAdjust software is available as free to download
software on the Mastervolt website: www.mastervolt.com. This tool runs on a Windows laptop or
notebook.

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

17

4.2.1 Monitoring

A remote panel, like the SmartRemote, Touch 5 (CZone) or EasyView 5 (MasterBus), can be used for
reading battery information. See applicable user manuals for details. The following table lists the
parameters as shown in MasterAdjust.

Parameter

Meaning

Value range

General

Device state

Shows charger state (On / Stand-by / Alarm / Off)

(read only)

Charger state

Actual state of charge process: Off/bulk/absorption/float/suspended

(read only)

'Toggle' button

Button to toggle the charger state.
This button does not work when the ChargeMaster Plus is switched

off manually. In that case it can only be switched on with the
ON/OFF button.

On / off

Input current

Option to set the maximum AC input current level to prevent a
generator or shore fuse from overload. See section 4.2.6 for more
information. Default 20.

12/35-3: 0-9A
12/50-3: 0-11A
24/20-3: 0-10A
24/30-3: 0-15A

AC present 

Shows the presence of AC input

(read only)

Battery temp.

Temperature of the main battery bank (in °C)

(read only)

DC 1 OUT

Output 1

Output state (pre-float/on)

(read only)

Output 1 V

Voltage of charge output 1

(read only)

Output 1 A

Output current of charge output 1

(read only)

Shunt device

A connected MasterShunt can be chosen for feedback on the
charged battery. Default not selected.

(read only)
DC 2 OUT

Output 2

Output state (pre-float/on)

(read only)

Output 2 V

Voltage of charge output 2

(read only)

Output 2 A

Output current of charge output 2

(read only)

DC 3 OUT

Output 3

Output state (pre-float/on)

(read only)

Output 3 V

Voltage of charge output 3

(read only)

Output 3 A

Output current of charge output 3

(read only)

 Parameters marked with a  are not available in CZone.

4.2.2 Alarms

The following table lists the available alarms in MasterAdjust.

Parameter

Meaning

Alarm status

Bat. temp. error

Battery temperature too high / too low

TS error

Temperature sensor error

AC error

AC input (mains) out of range

Dev. temp. high

ChargeMaster Plus temperature too high

DC 1 OUT

Shunt mismatch

Setting for nominal voltage (12/24V) at the MasterShunt or the nominal voltage of
the MLI batteries differs from nominal voltage detected by the ChargeMaster Plus.
Check battery voltage and settings of the MasterShunt or voltage of the MLI Ultra
battery.

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Parameter

Meaning

Reverse polarity

DC + and DC – are connected in reverse (this will damage the charger)

DC 2 / 3 OUT

Reverse polarity

DC + and DC – are connected in reverse (this will damage the charger)

4.2.3 History

The history data shows the absolute maximum readings. The following parameters are only shown in
MasterAdjust.

Parameter

Meaning

Charger

Days running

Total run time in charger mode

DC 1 / 2 / 3 OUT

Total Ah’s

Total charged Ah’s

4.2.4 Configuration settings

The configuration can be done in MasterAdjust, from a laptop or notebook connected to the
ChargeMaster Plus via a Mastervolt USB Interface. See applicable user manuals for details. The following
table lists the parameters as shown in MasterAdjust.

Notes: - DIP switch settings overrule MasterBus settings. If DIP switches are not in their default setting,

the corresponding MasterBus setting is grayed out.

- To be able to make changes to the configuration via MasterBus, DIP switch 1 must be in the

ON position.

Parameter

Meaning

Factory
setting

Value range

Device

Language

Menu language of this device

English

EN, NL, DE, FR, ES, IT, NO,
SV, FI, DA

Name

Name of this device. This name will be
recognized by all devices connected to
the network

CHG
ChargeMaster

0-12 characters

Powersave
mode

If Powersave mode is ON, the charger
will switch itself off when no AC power
is available.
If Powersave mode is OFF, the charger
stays ON even when no AC power is
available.

On

On, Off

Charger

Method

Charge method

3-Step+

3-Step+, constant voltage

Maximum
current

Maximum DC output current

Depending on
model, 100%

Depending on model 20­100%

Battery type

The battery type settings are based on
Mastervolt batteries. If connecting
batteries of a different manufacturer,
make sure the manufacturer's recom­mendations are met. Should this not be
the case, then "User defined" must be
selected to change the settings.

Flooded

User defined, AGM, Gel,
Flooded, Lithium-ion (MLI)

Temp.
compensate

Temperature depended charge voltage
compensation

-0,030V/°C /

-0,060V/°C

-1,000/+1,000V/°C

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

19

Parameter

Meaning

Factory
setting

Value range

Bulk

Voltage

Bulk voltage (@ 25°C); see section 5.4

14.40/28.80V

8-16/16-32V

Minimum
time

Minimum time of the Bulk phase since
Start bulk timer

120sec

0-240sec

Start time at

Battery voltage trigger point to start the
bulk timer

13.25/26.50V

(read only)

Maximum
time

Maximum time of the Bulk phase since
Start bulk timer

480 min

0-1440min

Absorption

Voltage

Absorption voltage (@ 25°C); see
section 5.4

14.25/28.50V

8-16/16-32V

Maximum
time

Maximum absorption timer

240min

0-1440min

Return
Amps

Return amps. If the charge current
drops below this level, the charger
switches from the Absorption to the
Float stage (% of I

max

)

6%

0-50%

Minimum
time

Minimum absorption timer

15min

0-240min

Float

Voltage

Float voltage (@ 25°C); see section 5.4

13.25/26.50V

8-16/16-32V

Return to
bulk
V

Return to bulk voltage; If the battery
voltage stays below this level for at least
the Return to bulk delay time, the
charger will start the Bulk stage

12.80/25.60V

8-16/16-32V
Return to

bulk
sec

Return to bulk delay time, see Return to
bulk voltage

30sec

0-240sec

DC 1 OUT

Name

Name of this output

Output 1

0-16 chars

Shunt
device

Selection of the MasterShunt to which
output 1 of the ChargeMaster Plus is
connected

Not selected

Not selected,
MSH + Product Name

DC 2 / 3 OUT

Name

Name of this output

Output 2 / 3

0-16 chars

Installer menu

DIP Switch

DIP switch settings

1100000000

0 / 1

Factory
settings
button

Button to reset the ChargeMaster Plus
to default settings (requires installer
rights)

Not
applicable

Not applicable

 Parameters marked with a  are not available in CZone.

4.2.5 Events – System automation

A CZone/MasterBus device can be programmed to initiate an action at another connected device. This is
very helpful in automation of your system but is not required.

In MasterBus this is done by means of event-based commands. In the Events tab you can program the
ChargeMaster Plus to act as an event source. Events which occur during the operation of the

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ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

ChargeMaster Plus will then trigger actions from other products. The following tables list the parameters
as shown in MasterAdjust.

Field

Meaning

Value

Event x source

Select an event that triggers an action, for
example Battery pre low.

See Event source list

Event x target

Select the device that should take action, for
example the generator

Selectable targets are
system dependent

Event x command

Select the parameter that must be changed on the
target device, for example Activate.

See command list of the
selected device

Event x data

Data, for example On, is linked to the command.

Off, On, Copy, Copy Invert,
Toggle

Table 1: MasterBus event parameters

The ChargeMaster Plus can be configured as an event source. An event source can be used to initiate
an event command and an event action by another device.

Event source

Meaning

Charger state

State of the ChargeMaster Plus serves as an event source

Bulk

Bulk state of charge serves as an event source

Abs

Absorption state of charge serves as an event source

Float

Float state of charge serves as an event source

Failure

Any fault condition of the ChargeMaster Plus serves as an event source

Table 2: ChargeMaster Plus MasterBus Event sources

When the ChargeMaster Plus is configured as an event target by another device, this device can initiate
an event command and an event action to be performed by the ChargeMaster Plus.

Event command

Meaning

On

Command to switch on the ChargeMaster Plus

Bulk

Command to start the Bulk state of charge

Abs

Command to start the Absorption state of charge

Float

Command to start the Float state of charge

Suspend charging

When using an MLI Ultra Li-ion battery, this event is obligatory. Refer to the MLI
Ultra manual.

Table 3: ChargeMaster Plus MasterBus Event commands

4.2.6 Current control

If the available power at the AC input is limited. The ChargeMaster can be configured to reduce input
current. The Current Control level should be set equal to or lower than the value of the external circuit
breaker, which protects the incoming AC power. For example, when the external AC power is limited by
a 6A fuse, the Current Control level should be set to ≤6A. The AC input current of the ChargeMaster Plus
will be reduced to 6A.

How to set the AC input current in a MasterBus network

1. Open MasterAdjust.

2. Select the ChargeMaster Plus.

3. Go to the Monitoring tab.

4. In the Input Current field, enter the required value.

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

21

4.3 MasterShunt

In a MasterBus network, a MasterShunt can be coupled with output 1 (DC 1 OUT) of the ChargeMaster
Plus. The actual measurement data of the MasterShunt will be used to charge the batteries. Refer to the
manual of the MasterShunt for information on how to configure your system.

4.4 Lithium-ion Battery MLI Ultra

The ChargeMaster Plus can be combined with a Li-ion battery MLI Ultra. Refer to the manual of the Li-ion
battery MLI Ultra for information on how to configure your system.

WARNING!

Before using the Li-ion battery, it must be properly installed and commissioned!

4.5 CZone configuration

The CZone® network is an NMEA 2000-compliant CAN-based system. When the ChargeMaster Plus is
connected, open the CZone Configuration Tool on a Windows laptop or notebook connected to the CZone
network. Either do the configuration while connected to the network or use a prepared configuration file
(.zcf). Ensure that a DIP Switch is assigned.

Adding the ChargeMaster Plus to a CZone system configuration
Precondition: This section assumes that a CZone system is already configured and the CZone

Configuration Tool is open.
In the CZone Configuration Tool, from the Modules tab, press the Add button.
From the Module Type drop-down list select Chargers.
From the Charge Type drop-down list select the required model and continue with the following steps.

1. Enter an understandable Module Name.

2. Each device on a CZone network has a unique CZone address; the Dipswitch. This number must

match the physical DIP switch settings. When connected to the system: either select one from the
drop-down list or edit graphically.

3. Select the Battery Type.

4. Enter the DC Current Limit.

5. Option: press the Advanced Settings button to configure advanced options.

6. Select the required Charge Method from the drop-down list.

7. Enter an understandable Name for DC 1 OUT, DC 2 OUT and DC 3 IN/OUT.

8. From the DC 3 Charge Method drop-down list, select the required charge method for DC 3 OUT.

See section 5.5. Depending on the selected charge method, additional settings will be offered,
hidden or grayed out.

9. NMEA2000 Instances are used to differentiate between multiple monitoring sources.

10. Press OK to return to the Module Modification window and press the Alarm/Switch Settings

button.

11. Select the required Alarm Severities.

12. Press OK.

Optionally configure digital switching by adding Circuit Controls in the Circuits tab (e.g. a battery low
switch can be used to start a generator). Write the configuration to the network to use the new
configuration.

For more information, please refer to the CZone® Configuration Tool Instruction manual. Also
see section 4.2 for a description of the same settings in MasterAdjust.

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ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

5 OPERATING INSTRUCTIONS

5.1 Introduction

The Mastervolt ChargeMaster Plus is a fully
automatic battery charger. This means that
under normal circumstances it can be left
switched on with AC power and batteries
connected. The ChargeMaster Plus is suitable
for charging of Li-ion and lead-acid batteries,
which may include maintenance-free, low
maintenance, AGM, gel or deep-cycle batteries.
It operates on both 240V and 120V.

WARNING!

The MLI charging voltages on this
charger fit the Mastervolt Li-ion
(MLI) batteries but do not necessa­rily fit other Li-ion batteries! Always
follow the instructions provided by
the battery manufacturer!

5.2 Switching on / off

The ChargeMaster Plus is activated by keeping
the ON/OFF button pressed for approximately 3
seconds. The MODE LED will illuminate green. If
necessary and if AC power is available, the
ChargeMaster Plus will start to charge the
batteries.

Note: Once switched on, the ChargeMaster Plus

automatically resumes operation after it
was disconnected from an AC source
temporarily.

By holding the ON/OFF button pressed again for
approx. 3 seconds, the ChargeMaster Plus will
switch off: the ChargeMaster Plus stops and the
MODE LED illuminates red. When the
ChargeMaster Plus was switched off, it can only
be activated by pressing the ON/OFF button
again.

WARNING!

Switching the ChargeMaster Plus off
or “stand-by” does not cut off the
connection to the batteries or the AC
source. This means that voltages are
still present inside the apparatus.

5.3 Status display

The status display at the front side of the
ChargeMaster Plus enables you to control the
charger and monitor the charging process.

Note: The ChargeMaster Plus can also be

monitored from a remote panel like the
Touch 5 (in a CZone network) or the
EasyView 5 (in a MasterBus network). See
section 4.2 for details.

Figure 5: ChargeMaster Plus status display

ON/OFF button

Hold MODE pressed for 3 seconds to

switch the charger on or off

NETWORK

Blinks when there is

network communication

MODE

Indicates ChargeMaster

Plus status

Battery 1, 2 & 3

Battery charge status

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

23

The status display has a 3-level menu. Menu
navigation is done by shortly pressing the
ON/OFF button. After each press the next menu
level is shown. The MODE LED color indicates
the level that is being shown.

Menu

MODE LED
color

Meaning

Level 1

Green

Status menu

Level 2

Orange

Output power menu

Level 3

Red

Error menu

Status

LED

State

Meaning

MODE

Solid green

ChargeMaster Plus
on

Solid red

ChargeMaster Plus
stand-by

Blink fast
red

Error, navigate to
error menu

Battery
1

Blinking fast
green

Battery in bulk stage

Blinking
slow green

Battery absorption
stage

Solid green

Battery in float stage

Battery
2

Blinking fast
green

Battery in bulk stage

Blinking
slow green

Battery absorption
stage

Solid green

Battery in float stage

Battery
3

Blinking fast
green

Battery in bulk stage

Blinking
slow green

Battery absorption
stage

Solid green

Battery in float stage

Network

Blinking
green

Network
communication

Output power

LED

State

Meaning

MODE

Solid
orange

Output power menu

Battery
1

Solid
orange

Total output power 0­25%

Battery
2

Solid
orange

Total output power 26­50%

Battery
3

Solid
orange

Total output power 51­75%

Network

Solid
orange

Total output power 76­100%

Error

LED

State

Meaning

What to do

MODE

Blink
fast red

Error menu

Battery
1

Blink
fast red

Reverse
polarity

Check
battery
connection

Battery
2

Blink
fast red

AC error

Check AC
voltage/
frequency

Battery
3

Blink
fast red

DC error

Check
battery
voltage

Network

Blink
fast red

Tempera­ture sense
error

Check
temperature
sensor

5.4 The 3-step+ charge process

Battery charging is accomplished in three
automatic stages: BULK, ABSORPTION and FLOAT.

The first step is the BULK phase, in which the
output current of the charger is 100%, and the
greater part of the capacity of the battery is
rapidly charged. The current charges the
batteries and gradually the voltage rises to the

BULK voltage 14.25V respectively 28.5V at

25°C/77°F.
The duration of this phase depends on the ratio

of battery to charger capacity, and the battery
state of charge.

Figure 6: charge process

The BULK phase is followed by the ABSORPTION
phase. Absorption charging starts when the
voltage on the batteries has reached the BULK
voltage and ends when the battery is completely
full. Battery voltage remains constant at

14.25V/28.5V at 25°C/77°F throughout this
stage, and the charge current depends on the
degree to which the battery was initially

24

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

discharged, the battery type, the ambient
temperature, etc. With a flooded battery this
stage lasts approx. 4h, with gel and AGM around
3h. Once the battery is 100% full, the
ChargeMaster Plus automatically switches over
to the FLOAT phase. In FLOAT, the ChargeMaster
Plus switches to a stabilized 13.25V/26.5V
(Flooded), 13.8V/27.6V (Gel/AGM) or 13.5V/27V
(MLI) at 25°C/77°F.

Connected DC loads are powered directly by the
charger. If the load exceeds the charger
capacity, the required additional power comes
from the battery, which will be progressively
discharged until the charger automatically
switches back to the bulk phase. Once
consumption decreases, the charger goes back
to normal operation of the 3-step charge system.

As the ChargeMaster Plus is equipped with a 3­step+ charge system, the batteries can also
remain connected to the ChargeMaster Plus
during winter. One hour every 14 days the
charger automatically switches to absorption to
keep the battery running properly and prolong its
life span. The three-step plus charge system is
also safe for all the connected equipment. See
also Figure 9 on page 31.

5.4.1 Charge voltages

Bulk

Absorption

Float

AGM or
GEL

14.25 /

28.5

14.25 /

28.5

13.80 /

27.6

Flooded

14.25 /

28.5

14.25 /

28.5

13.25 /

26.5

Lithium-ion

14.00 /

28.0

14.00 /

28.0

13.50 /

27.0

5.4.2 Pre-float

The ChargeMaster Plus can automatically switch
each individual output from absorption to pre­float stage. Pre-float ensures batteries that are

nearly full don’t receive the higher charge

voltage needed in the absorption stage. This
prevents over-charging, extending the lifespan of
the batteries.

5.4.3 Temperature compensated charging

By installing the battery temperature sensor, the
charge voltages are automatically adapted for
deviating temperatures.

Charge voltage (V)

Battery temperature (°C)

Figure 7: Temperature compensated charging

When the battery temperature is low, the charge
voltage increases. On the other hand, when the
battery temperature is high, the charge voltage
is decreased. Overcharge and gassing are
prevented this way. This will extend the life of
your batteries.

5.4.4 Flat battery support

The ChargeMaster Plus automatically detects a
flat battery and will initiate the flat battery charge
curve described in the following table.

UBat

Voltage

Output power

12V
24V

0.00V – 2.50V

0.00V – 5.00V

15%-30% of I

max

12V
24V

2.50V – 8.00V

5.00V – 16.00V

25% of I

max

12V
24V

8.00V – 10.00V

16.00V – 20.00V

linear from 25% ­100% of I

max

12V
24V

10.00V – 14.25V

20.00V – 28.50V

100% of I

max

12V
24V

>14.25
>28.50

Limited by P

max

5.5 DC OUT

The ChargeMaster Plus is equipped with three
full outputs; DC 1 OUT, DC 2 OUT and DC 3 OUT. The
total output current is divided over these three
outputs. All batteries are charged with the same
settings. See section 3.6 for connections.

5.6 Maintenance

No specific maintenance to the ChargeMaster
Plus is required. Examine your electrical
installation on a regular basis, at least once a
year. Defects such as loose connections, dam­aged wiring etc. must be corrected immediately.
If necessary, use a soft clean cloth to clean
enclosure of the ChargeMaster Plus. Do not use
any liquids or corrosive substances, such as
solvents, alcohol, petrol or abrasive components.

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

25

5.7 Storage

If it is necessary to put the ChargeMaster Plus
out of operation, execute the following steps:

1 Turn AC power off.
2 Switch off the ChargeMaster Plus (see

section 5.2).

3 Remove the DC fuse(s) and disconnect the

batteries.

4 Switch the RCD/Breaker of the AC input to

the OFF position and, if required, disconnect
the AC mains.

5 Open the connection compartment of the

ChargeMaster Plus.

6 Check with a suitable voltage meter whether

the inputs and the outputs of the
ChargeMaster Plus are voltage free.

7 Disconnect all the wiring.

Now the ChargeMaster Plus can be demounted
in a safe way. When not installed, store the
ChargeMaster Plus in a dry and dust free
environment. To return to normal operation, after
re-installation, switch on the AC.

26

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

6 TROUBLE SHOOTING

The ChargeMaster Plus is protected against overload, short circuit, overheating and under and over
voltage. If a fault condition occurs, the LEDs indicate an error code. See section Status display for an
explanation.

CAUTION!

The ChargeMaster Plus is not protected against serious over voltage (>275VAC) on
the AC input.

If you cannot solve a problem using the fault-finding table, contact your supplier or Mastervolt. Make sure
you have the part and serial number at hand.

Malfunction

Possible cause

What to do

No output voltage
and/or current

No AC input

Check AC wiring, check remote control
panel

AC input voltage too low (< 75VAC)

Check input voltage, check generator

AC input frequency out of range

Check input voltage, check generator

Output voltage too
low, charger
supplies maximum
current

Load connected to the batteries is
larger than charger can supply

Reduce load taken from the batteries

Batteries not 100% charged

Measure battery voltage. After some time
this will be higher

Wrong setting of the charge
voltage

Check settings (see chapter 4)

Charge current too
low

Batteries almost fully charged

Nothing, this is normal when the battery
is almost fully charged

High ambient temperature

Nothing; if ambient temperature is more
than the setting limit, the charge current
is automatically reduced

Low AC input voltage. At lower AC
input voltages, the charge current
is reduced

Check AC input voltage

Batteries not fully
charged

Charge current too low

See “Charge current too low” in this

table

Current to load is too high

Reduce load taken from the batteries

Charge time too short

Use a battery charger with higher
capacity

Battery temperature too low

Use the battery temperature sensor

Defective or old battery

Check battery and replace if necessary

Wrong setting of the charge
voltage

Check settings (see chapter 4)

Batteries are
discharged too fast

Battery capacity reduced due to
wastage or sulphation, stagnation

Charge and recharge a few times, this
might help.

Check battery and replace if necessary

Batteries are too
warm, gassing

Defective battery (short circuit in
cell)

Check battery and replace if necessary
Battery temperature too high

Use the battery temperature sensor

Charge voltage too high

Check settings (see chapter 4)

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

27

Malfunction

Possible cause

What to do

Remote panel
display shows no
ChargeMaster Plus

Display is switched off

Switch on display, refer to display manual

Error in the wiring

Check the network cables

No terminating device placed at the
ends of the network

A network needs a terminating device on
both ends of the network, check if
available

Network is configured as a ring
network

Ring networks are not allowed. Check the
connections of the network.

ChargeMaster Plus is not
configured in CZone configuration
file

Open CZone Configuration Tool and
check.

ChargeMaster Plus Dipswitch not
correct

Open CZone Configuration Tool and
check with Force Dipswitch for Address.

Slow or no
MasterBus
communication.

Error in the MasterBus wiring

Check the network cables

No MasterBus Terminator placed at
the ends of the network

MasterBus needs a terminating device on
both ends of the network. Check if
connected

MasterBus network is configured
as a ring network or there are T­connections

Ring networks and T-connections are not
allowed. Check the connections of the
network

28

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

7 TECHNICAL DATA

7.1 Specifications 12V models

Model

12/35-3

12/50-3

Product code

44310355

44310505

Nominal input voltage

120/240V

120/240V

Nominal input frequency

50/60Hz

50/60Hz

Full load consumption

600VA

850VA

Max. AC input current (@ 230VAC)

2.5A

3.5A

Max. AC input current (@ 120VAC)**

5.0A

7.1A

Nominal output voltage

14.25V

14.25V

Total charge current*

35A at 14.25V

50A at 14.25V

Number of battery outlets

3 3 Charge characteristic*

IUoUo, automatic, 3-step+

Charge voltage Bulk*

14.4V

14.4V

Charge voltage Absorption*

14.25V

14.25V

Charge voltage Float*

13.25V

13.25V

Max absorption and max bulk timer*

8 hours (start max. bulk timer at 13.25V)

Minimum absorption time*

15 min.

15 min.

Maximum ripple voltage on DC

180mV pp

180mV pp

Battery type settings*

Flooded (default), GEL, AGM, Lithium-ion (MLI), Constant voltage
(13,25 V)

Dimensions (mm)

291×210×105

291×210×105

Dimensions (inch)

11.5×8.3×4.1

11.5×8.3×4.1

Weight

2,5 kg (5.5 lbs)

2,5 kg (5.5 lbs)

Recommended battery capacity

70-300Ah

100-400Ah

Power factor regulations

≥ 0,98

≥ 0,98

Temperature compensation

Battery temperature sensor and cable included.

Voltage compensation

Yes, by means of automatic compensation or MasterShunt

DC consumption

<2mA (MasterBus off)

<2mA (MasterBus off)

Temperature range

–25°C (–13°F) to 80°C (176°F)
Derating 1%/°C (0.5%/°F) from 40°C (104°F) to 60°C (140°F)
Derating 8%/°C (4.4%/°F) from 60°C (140°F) to 70°C (158°F)
Communication available, 0% output power from 70°C (158°F) to
80°C (176°F)

Cooling

Vario fan and natural cooling to ensure optimized cooling

Sound level

<45dBA / 1m

Protection degree

IP 23

IP 23

CZone connectivity

Yes

Yes

MasterBus connectivity

Yes

Yes

Powering capabilities for MasterBus

Yes

Yes

Yes, when the charger is switched on and AC is available, it can
power up to three non-powering devices.

Ignition protected

Yes, conforming to SAE J1171/ISO 8846

* Adjustable, see chapter 4 for settings.
** The input RCD/Fuse rating selection must be greater than 120% of the max input current (@ 120VAC)

or in accordance with the requirements of national electrical regulations.

Specifications are subject to change without prior notice.

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

29

7.2 Specifications 24V models

Model

24/20-3

24/30-3

Product code

44320205

44320305

Nominal input voltage

120/240V

120/240V

Nominal input frequency

50/60Hz

50/60Hz

Full load consumption

700VA

1000VA

Max. AC input current (@ 230VAC)

2.8A

4.2A

Max. AC input current (@
120VAC)**

5.6A

8.6A

Nominal output voltage

28.5V

28.5V

Total charge current*

20A at 28.5V

30A at 28.5V

Number of battery outlets

3

3

Charge characteristic*

IUoUo, automatic, 3-step+

Charge voltage Bulk*

28.8V

28.8V

Charge voltage Absorption*

28.5V

28.5V

Charge voltage Float*

26.5V

26.5V

Max absorption and max. bulk
timer*

8 hours (start max. bulk timer at 26.5V)
Minimum absorption time*

15 min.

15 min.

Maximum ripple voltage on DC

300mV pp

300mV pp

Battery type settings*

Flooded (default), GEL, AGM, Lithium-ion (MLI), Constant voltage
(13,25 V)

Dimensions (mm)

291×210×105

291×210×105

Dimensions (inch)

11.5×8.3×4.1

11.5×8.3×4.1

Weight

2,5 kg (5.5 lbs)

2,5 kg (5.5 lbs)

Recommended battery capacity

160-400Ah

200-500Ah

Power factor regulations

≥0,98

≥ 0,98

Temperature compensation

Battery temperature sensor and cable included.

Voltage compensation

Yes, by means of automatic compensation or MasterShunt

DC consumption

<2mA (MasterBus off)

<2mA (MasterBus off)

Temperature range

–25°C (–13°F) to 80°C (176°F)
Derating 1%/°C (0,5%/°F) from 40°C (104°F) to 60°C (140°F)
Derating 8%/°C (4,4%/°F) from 60°C (140°F) to 70°C (158°F)
Communication available, 0% output power from 70°C (158°F) to
80°C (176°F)

Cooling

Vario fan and natural cooling to ensure optimized cooling

Sound level

<45dBA / 1m

Protection degree

IP 23

IP 23

CZone connectivity

Yes

Yes

MasterBus connectivity

Yes

Yes

Powering capabilities for
MasterBus

Yes

Yes

When the charger is switched on and AC is available, it can power
up to three non-powering devices.

Ignition protected

Yes, conforming to SAE J1171/ISO 8846

* Adjustable, see chapter 4 for settings
** The input RCD/Fuse rating selection must be greater than 120% of the max input current (@ 120VAC)

or in accordance with the requirements of national electrical regulations.

Specifications are subject to change without prior notice.

30

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

7.3 Dimensions

Dimensions in mm [inches] of the ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3.

7.4 Characteristics

Output power (%)

AC voltage (V)

Figure 8: Output power versus input voltage

ChargeMaster Plus 12/35-3, 12/50-3, 24/20-3, 24/30-3 – User and Installation Manual

31

Figure 9: 3-step+ charging characteristics of flooded batteries

Europe, Middle East & Africa

Customer Service

T: [phone]
E: [e-mail]

Technical Support

T: [phone]
E: [e-mail]

Location & Shipping

Mastervolt
Snijdersbergweg 93
1105 AN Amsterdam
The Netherlands

Americas & Caribbean

Customer Service

T: [phone], Option 1
E: [e-mail]

Technical Support

T: [phone], Option 2
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Location & Shipping

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Menomonee Falls, Wisconsin 53051
United States

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Customer Service

T: [phone] Option 1
E: [e-mail]

Technical Support

T: [phone] Option 3
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Location & Shipping

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New Zealand

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