MASTERVOLT MLI Ultra 1250 12 V / 100 Ah Lithium Charger/Inverter Combo Pack, MLI Ultra 1250 12V/100Ah Lithium Pack, Lithium Boat Battery 12V / 24V / 100Ah MLI ULTRA, Lithium Expert System - 12V/100Ah Lithium Battery, ChargeMaster 12/25-3, SmartRemote Display and 200A fuse Manual

MLI Ultra

LITHIUM-ION BATTERY

12/1250, 24/1250

USER AND INSTALLATION MANUAL

10000018055 /01

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2

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

Table of contents

1. SAFETY INSTRUCTIONS .................... 3

Safety warnings ..................................... 3

Safety guidelines ................................... 4

2. GENERAL INFORMATION ................... 5

Liability .................................................. 5

Warranty ............................................... 5

Disclaimer ............................................. 5

Identification label ................................. 5

Correct disposal of this product ............. 5

3. PRODUCT DESCRIPTION ................... 6

Status LEDs .......................................... 6

Battery switch-button (safety

disconnect) ........................................... 7

Battery Management System (BMS) ..... 8

Charging ............................................... 8

4. BASIC INSTALLATION ......................... 9

Unpacking ............................................. 9

Location ................................................ 9

Materials needed ................................. 10

Installation procedure for a single unit . 10
Adding the MLI Ultra to a MasterBus

network ............................................... 12

Adding the MLI Ultra to a CZone

network .............................................. 12

Auxiliary connector .............................. 13

5. CONFIGURATION .............................. 14

DIP switch settings .............................. 14

MasterBus DIP switch settings ........... 14

CZone DIP switch settings ................. 14

How to change the DIP switch

settings ............................................. 15

Configuration in a MasterBus network . 15

Monitoring tab .................................... 15

Alarms tab .......................................... 16

History tab .......................................... 16

Configuration tab ................................ 17

Events tab .......................................... 18

Events sources ................................... 20

Event commands ................................ 21

Stop Charge event .............................. 21

Configuration in a CZone network ........ 22

6. BUILDING A BATTERY BANK ............ 24

Series and parallel connections ........... 24

Configuration of a battery bank ............ 25

Using DIP switches (MasterBus only) . 25

Using MasterAdjust ............................ 27

Using CZone Configuration Tool......... 28

7. STORAGE AND CARE ........................ 29

8. TROUBLESHOOTING ......................... 30

9. SPECIFICATIONS ............................... 32

Technical specifications ....................... 32

Battery switch – automatic behavior .... 33

Characteristics ..................................... 34

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

3

1. SAFETY INSTRUCTIONS

IMPORTANT SAFETY INSTRUCTIONS
SAVE THESE INSTRUCTIONS

Safety warnings

WARNING!

The battery contains hazardous materials that are stored safely
during normal use. Do not crush, open or drop the battery
housing. Do not touch or ingest any of the released materials or
inhale released gasses when accidental leakage of the battery
occurs. Should skin contact, eye contact or inhalation neverthe­less occur, take the necessary first aid measures immediately.
Refer to the Material Safety Data Sheet for Mastervolt Lithium­Ion batteries, which is available on www.mastervolt.com.

WARNING!

Avoid short circuiting batteries as this may result in fire,
explosion, electric shock or release of toxic gas. Use insulated
tools only and keep metal objects away from the battery. Do not
wear watches, bracelets, necklaces or other metal objects when
working on the battery. In case of fire, take the necessary
firefighting measures immediately. Refer to the Material Safety
Data Sheet for Mastervolt Lithium-Ion batteries, which is
available on www.mastervolt.com.

WARNING!
Short circuits, too deep discharges and too high charge currents
will damage the battery and may result in fire, explosion, electric
shock or release of toxic gas. Never charge a battery:

- after it was discharged below the Battery Safety voltage;

- when the battery is damaged;

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MLI Ultra 12/1250, 24/1250 – User and Installation Manual

- when the battery was over-charged.

If in doubt, contact your Mastervolt dealer.

CAUTION!
When transported, make sure that:

- the battery is in its original package or equivalent;

- the battery is in upright position;

- soft slings are used to avoid damage;

- the battery is only lifted at the handles;

- the battery is handled with care.

Note: The voltage range (12.0-14.6V or 24.0-29.2V) is larger than you may expect from other

battery types such as lead-acid batteries. Be aware that these voltages could exceed
the permitted voltages of the connected load(s).

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.

Safety guidelines

- Use the MLI Ultra following the instructions and specifications stated in this manual.

- Work on the MLI Ultra should be carried out by qualified personnel only.

- Non-compliance with operating instructions, repairs made with other than original parts, or repairs
made without authorization render the warranty.

- If programming of events in a MasterBus or CZone network is required, the installer must be
familiar with the programming of such events.

- Connections and safety features must always comply with all local rules and regulations.

- Use cables with an appropriate size.

- Never use the MLI Ultra in situations where there is danger of gas or dust explosion or potentially
flammable products!

- Only use the MLI Ultra in a technical correct condition.

- Only use the MLI Ultra in a well-ventilated area and protect the connectors from moisture and
dust.

- Switch off all charging systems and disconnect the MLI Ultra from the electrical installation during
maintenance and/or repair activities.

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

5

2. GENERAL INFORMATION

Liability

Mastervolt cannot be held liable for:

- Consequential damage resulting from the use of the MLI Ultra.

- Possible errors in the included manual and the consequences of these.

- Use that is inconsistent with the purpose of the MLI Ultra.

Warranty

The Mastervolt product warranty covers the MLI Ultra 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 does 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.

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 online Terms & Conditions of Sale.

Identification label

The following picture is only an example!

The identification label is located on the top side of the MLI Ultra.
Technical information required for service and maintenance (part
number, serial number and revision code) can be derived from
the identification label.

CAUTION!

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

Correct disposal of this product

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

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MLI Ultra 12/1250, 24/1250 – User and Installation Manual

3. PRODUCT DESCRIPTION

1. M8 positive terminal

2. M8 negative terminal

3. Provision for removable handle

4. Hold down edges group 31, fit battery group size 49

5. Attachment strap support

6. Protective vent; maintain adequate ventilation around
this opening. Do not touch the membrane!

7. Auxiliary connector

8. MasterBus/CZone connectors

9. Status LEDs and DIP switch
cover

10. Battery switch-button (safety

disconnect)

Figure 1: overview of the MLI Ultra 1250

Status LEDs

Figure 2: status LEDs

10

9

7 2 6 5 3

8

4

1

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

7

LED

Color

Name

Behavior

A

Red

Error

If this LED is on, a BMS error has occurred or cells are damaged.
Check the installation and contact your Mastervolt dealer.

B

Yellow

Battery
state

During normal operation the LED is off.

1 short blink

● ● ●

State of Charge (SoC) low. Charge the
battery.

2 short blinks

●● ●● ●●

CZone network identification (during
installation).

3 short blinks

●●● ●●●

Auto cluster configuration error. See section
"Using DIP switches" on page 25.

4 short blinks

●●●● ●●●●

Battery is executing a recovery procedure.

Blinking slowly

▬ ▬ ▬

Battery is updating its firmware.

C Green

Battery
switch
state

When the Battery switch-button is pressed short, this LED indicates
the status of the battery switch.

- Solid on for 1 minute: battery is on (switch is closed).

- Blinking for 1 minute: battery is off (switch is open).

Battery switch-button (safety disconnect)

CAUTION!

This built-in battery switch is to safely disconnect the battery. It also disconnects
from the charger!

Figure 3: Battery switch-button
Press short for status; Short press to make LED C show the status of the Battery switch.

• Solid on for 1 minute: battery is on (switch is closed).

• Blinking for 1 minute: battery is off (switch is open).

Press 1 sec; Long press for 1 second to switch-off. LED C will blink.
Press 5 sec; Long press for 5 seconds to switch-on. LED C will light up for 1 minute.
Note: If the battery was switched-off manually, it must be switched-on manually.

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MLI Ultra 12/1250, 24/1250 – User and Installation Manual

Battery Management System (BMS)

The MLI Ultra has a built-in Battery Management System (BMS) and a built-in battery switch. The
BMS protects the battery by automatically controlling the battery switch when thresholds are met.
This is called a 'battery safety'-event. See chapter "SPECIFICATIONS” for the thresholds. An
automatically switch-off is initiated after the following events:

• Cell over- or under-voltage

• Battery over-current

• Over-temperature of the MLI Ultra

• Low State of Charge (SOC)

Likewise, automatically switch-on is initiated when the conditions are safe again.

Charging

The MLI Ultra can be charged with any Mastervolt battery charger, like the ChargeMaster Plus
series, or with a ProMariner ProSport HD or ProNautic for example. Make sure that the charger is
Lithium Ion compatible and meets the MLI Ultra's charge parameters. Set the battery type to MLI or
adjust the 3-step+ (also known as IuoUo) charge characteristic as follows:

Model

Bulk / absorption voltage

Float voltage

12V

14.25 V

13.5 V

24V

28.5 V

27 V

LED B will blink yellow when the state of charge (SOC) is low. Make sure to charge when the SOC
is low to preserve the lifespan.

Recovering from deeply discharge

If the MLI Ultra was deeply discharged, the integrated 1A charger charges the cells to 2.5V. After
that, a self-test on the cells will activate automatically to test if the cells are damaged by the deep
discharge. When the result is ok, the battery will be switched-on, and normal charging can start.
When the result is not ok, LED A will be solid red. In that case, contact your Mastervolt dealer.
Please note that this procedure may take between 30 minutes to 5 hours!

Charging at low temperature

Do not use a sensor for temperature compensated charging. Temperatures of the battery and its
cells are monitored by the built-in BMS. If the temperature of the MLI Ultra is below 0°C [32°F], an
integrated heater is automatically turned on until 5°C [41°F] is reached or the charger is
disconnected. This heater can also be controlled through MasterBus events or CZone circuits.

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

9

4. BASIC INSTALLATION

Unpacking

The delivery consists of the following parts:

1. MLI Ultra battery with 2x M8 bolt + washer + spring washer, for screw connection

2. 1x automotive battery pole positive (thick) + M8 Allen bolt, for clamp connection

3. 1x automotive battery pole negative (thin) + M8 Allen bolt, for clamp connection

4. Handle

5. 2x Attachment strap (for stationary applications only)

6. MasterBus terminator

7. MasterBus cable (1m)

8. Drop cable CZone/MB (1m)

9. Auxiliary cable (2m)

10. The quick installation manual
Never use a damaged battery. If in doubt, contact your Mastervolt dealer.

Location

- Install the MLI Ultra in a well-ventilated room protected against rain, snow, spray, vapor, bilge,

moisture and dust.

- Keep the MLI Ultra away from heat sources. See specifications for allowed operating

temperatures.

- The MLI Ultra must be installed in upright position or on the long side of the case, although upright

mounting is recommended.

Upright position

Long side position

- Keep at least 1cm [3/8"] between two Li-Ion batteries for air flow.

- The MLI Ultra must be secured. The following drawings are examples of mounting options:

With included mounting

straps (stationary

applications only)

Hold-downs on long side

(group 49)

With a frame or tray

11 mm

0.4 inch

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MLI Ultra 12/1250, 24/1250 – User and Installation Manual

Materials needed

- Battery charger

- Due to Interrupt Rating, use a T-fuse or an MRBF fuse and a fuse holder.

This manual assumes that an MRBF fuse is used.

- DC wiring

MLI Ultra 12/1250

MLI Ultra 24/1250

Recommended fuse

200 A

100 A

Recommended wire size

70 mm2 [AWG 2/0]

35 mm2 [AWG 2]

WARNING!

The wire and fuse sizes stated in this manual are only guidelines. Cross section
depends on the maximum system current.

Always comply with all local rules and regulations.

Installation procedure for a single unit

WARNING!

In installations with a negative earth: Connect the negative cable last of all to
prevent short circuiting.

WARNING!
Never mount a stud fuse directly to the battery terminal without a fuse holder! If there
is not enough space, use a separate bus bar to mount the fuse on.

Step 1. Switch off all loads and chargers.
Step 2. Insert the handle into the recesses on the top of the battery.

Step 3. Out of the box, the battery is on (switch is closed). Press the Battery switch-button to

switch-off (safety disconnect). LED C will blink for 1 minute to indicate that the battery is off

(switch is open).
Step 4. Secure the battery in place.
Step 5. Mount an MRBF fuse holder directly on the battery's POSITIVE terminal, add the fuse and

the POSITIVE cable. Tighten the bolt. Never mount a stud fuse directly on the battery

terminal. Always use the isolated fuse holder! Otherwise the fuse will not work! See the

following figure.

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

11

A. + terminal

B. Fuse holder
C. Fuse
D. Positive cable
E. Plain washer
F. Spring washer

Figure 4: mounting a stud fuse

Connect the negative cable to the – terminal.

Recommended torques: 14.7 – 19.6 Nm / 130 – 170 InLbs.
Step 6. Option: connect the 6-pin auxiliary connector cable. See page 13 for details.

Step 7. Option: connect communication cables.

- MasterBus: connect two MasterBus cables (or one cable and one
Terminator). See Figure 5 on page 12.

- CZone: connect the drop cable. On the battery side, plug the connectors
into either of the communication ports. See Figure 6 on page 13.

Step 8. Press the Battery switch-button for 5 seconds to switch the battery on. LED C will be solid

on for 1 minute to indicate that the switch is closed.

Step 9. Switch on some loads and verify that they are working. Switch off the load, switch on the

charger and verify (charger status) that the battery is being charged.

To change the default settings according to your needs, either use the DIP switches or a
configuration tool. For optimal use, it is strongly recommended to configure a Stop charge event.
See page 21 for more information.

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MLI Ultra 12/1250, 24/1250 – User and Installation Manual

Adding the MLI Ultra to a MasterBus network

MasterBus is a CAN based, fully decentralized data network for communication between Mastervolt
devices. MasterBus is used as power management system for all connected equipment, such as the
inverter, battery charger, generator and many more. Every device that is compatible with MasterBus
is equipped with two data ports. The devices are simply daisy chained together, forming a local data
network

1. Disconnect a MasterBus cable or Terminator from the closest MasterBus device and connect it
to the MLI Ultra.

2. Connect the new MasterBus cable to the other MasterBus device and then connect to the MLI
Ultra.

3. Ensure that the network is properly terminated.

Figure 5: MasterBus cables

Adding the MLI Ultra to a CZone network

The CZone network is an NMEA 2000-compliant CAN-based system. In a CZone network, the MLI
Ultra can be monitored from a remote panel like the Touch 5. The settings can only be adjusted with
the CZone Configuration Tool.

Additional required materials per MLI Ultra:

1. Disconnect the backbone at the closest backbone connection and add in a tee connector (not
included).

2. Reconnect the backbone connection(s) with the new tee connector in place. Ensure that the
network is properly terminated.

3. Connect the RJ45 CZone/MB drop cable to the black coupler on the tee and then connect to the
MLI Ultra. On the battery side, plug the connectors into either of the communication ports. LED
B will blink to confirm CZone network identification.

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

13

Figure 6: CZone drop cable

Auxiliary connector

FUNCTION

WIRE COLOR

PIN

Figure 7: connector

on the MLI Ultra

Analog SoC output

Max rating: 1mA

Green (0 – 10VDC)
Black (GND)

6 3 Aux. relay
Max rating: 30VDC/1A

Yellow
White

4 5 Not used

Red
Blue 1 2

Figure 8: six wire ferruled auxiliary cable

• State of Charge (SoC) indication

Wire pair 3&6 can be used to monitor the SoC on external equipment, where 10V = 100% and
0V = 0%. To enable this, select the "SOC 0-10V" option in the Configuration tab, see page 17.

• Auxiliary relay (dry contact)

Wire pair 4&5 can be used to control an external device like a switch, relay or lamp. This is done
in combination with a MasterBus event command or CZone circuit.

RED

BLUE

YELLOW

GREEN

BLACK

WHITE

GND

GND

VDC

0-10V

RELAY

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MLI Ultra 12/1250, 24/1250 – User and Installation Manual

5. CONFIGURATION

Out of the box, the MLI Ultra is suitable for use in a MasterBus network or as a stand-alone battery.
For CZone and for advanced features, the settings must be adjusted. Most settings can be done
through DIP switches. Advanced or network settings are done from a Windows laptop or notebook
with either the free MasterAdjust or the CZone configuration tool. MasterAdjust software can be
downloaded at www.mastervolt.com. The CZone Configuration Tool software is available to
technical CZone customers from the CZone Portal.

DIP switch settings

By default, all DIP switches are off.

MasterBus DIP switch settings

1. Set DIP switches 1 and 2 ON (1).

2. Set DIP switches 3 to 8 to fit your needs. DIP switches 9 and 10 are not used in MasterBus.

DIP switch

3 4 5 6 7

8

Event-based 'stop charge' can be setup per charger:
Automatic 'stop charge' for ALL Mastervolt chargers:

(see also section "Stop Charge event" on page 21)

0 1

Cluster setting for multi-unit configuration

Stand-alone:

Replica unit:
Primary 12V unit:
Primary 24V unit:
Primary 36V unit:
Primary 48V unit:

(see section "Configuration of a battery bank” on page 25)

0
0
0
0
1
1

0
0
1
1
0
0

0
1
0
1
0
1

'Auto switch-on' enabled:

'Auto switch-on' disabled:

0 1

'Battery detect' disabled:

'Battery detect' enabled:

0
1

Battery detect: If the battery is switched-off, there will be no voltage at the poles and some chargers
will not start charging. By enabling the Battery detect option, this is fixed. Note if a load is connected
that this will slowly drain the battery (5-10mA).

CZone DIP switch settings

1. Set DIP switch 1 to the OFF position (0).

2. Set DIP switch 2 to the OFF position (0).

3. Set DIP switches 3 to 10 to match the unique 'dipswitch' number, used in the CZone network.

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

15

How to change the DIP switch settings

Figure 9: DIP switches

1. Remove the DIP switch cover by loosening the four screws.

2. Use a small screwdriver to carefully change the DIP switch position.

3. Replace the DIP switch cover and fasten with the screws. Make sure that the rubber band is
placed correctly, to make it watertight.

Configuration in a MasterBus network

A display like the SmartRemote or EasyView 5, can be used to monitor the MLI Ultra. Advanced
configuration can be done in MasterAdjust, from a Windows laptop or notebook connected to the
MLI Ultra via a Mastervolt USB Interface. The following tables list the parameters as shown in
MasterAdjust.

Monitoring tab

Menu

Description

Battery/Cluster

State of charge

Battery state of charge in %

Time remaining

Time of battery use left at the actual load in hh:mm:ss

Voltage

Battery voltage measured by the cell management system

Current

Current measured by the cell management system
Positive value: charging, negative value: discharging

Temperature

Internal temperature of the battery in °C

Battery switch

Switch close

Button to close the battery switch.

Switch open

Button to open the battery switch.

Switch state

State of the battery switch: open / close / unknown

Note: you need to login as installer to see all following parameters.

Installer

Battery safety

Indication of the occurrence of a Battery Safety event

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MLI Ultra 12/1250, 24/1250 – User and Installation Manual

Menu

Description

Stop charge

Indication of the occurrence of a Stop charge event

MB power state

Indication whether MasterBus powering is on or off

Heater

This checkbox is marked when the heater is on

Aux. relay close

Closure of relay wire pair 4&5 of the auxiliary cable

Aux. relay open

Opening of relay wire pair 4&5 of the auxiliary cable.

Voltage

Cell 1 … 8

Voltage of the individual cells

Balancer

Balancer 1…8

Indication of balancing of the individual cells

Temperature

Temperature

Temperature of cells 1, 2-3, 4-5, 6-7, 8

Alarms tab

Menu

Description

Generic

Battery safety

Indication of the occurrence of a Battery Safety event

Overcurrent

Battery current too high

Short circuit

Indication of a short circuit in the MLI Ultra

Capacity low

This alarm is raised when the State of charge (SoC) drops below a preset
value (10% by default)

Cap. Very low

Indicates that the State of charge drops below a preset value (0% by default)

Note: you need to login as installer to see all following parameters:

BMS failure

BMS error

Bat. switch err.

Battery switch error

Recovery failed

This checkbox is marked when the battery recovery has failed

Recovery active

This checkbox is marked when the battery is recovering

History tab

Menu

Description

Cycle count

The number of cycles so far

Last time 100%

Date of the last time that the MLI Ultra was fully charged

Max. Ah used

The maximum used capacity that the MLI Ultra saw

Lowest voltage

The lowest battery voltage that the MLI Ultra saw

Highest voltage

The highest battery voltage that the MLI Ultra saw

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

17

Configuration tab

Menu

Description

Default

Adjustable
range

Name

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

MLI[serial
number]

0-12 chars
Language

Menu language of this device

English

English, Dutch

Serial number

Serial number of the MLI Ultra

(read only)

DIP switches

Status of the DIP switches

0

(read only)

CZone

This checkbox is marked when the MLI
Ultra is setup to work in a CZone network

(read only)

MB power

Off: MasterBus powering disabled.
Automatic: MasterBus power will be

switched off when the main current is in
between 1.0A and -1.0A for more than 24
hours and the battery voltage has dropped
below the float voltage.
Always on: the MLI Ultra will power the
MasterBus network. Note that this will
slowly drain the battery.
Note: MasterBus powering is only available
if DIP switch 2 is ON.

Off

Off / Automatic /
Always on

Auto switch on

Select this option for automatic control of
the battery switch.

On

On/off

Auto heater

Select this option for automatic control of
the heater.

On

On/off

Processor

Version

Firmware main version

(read only)

Revision

Product version

(read only)

Bootloader ver.

Bootloader version

(read only)

Note: you need to login as installer to see all following parameters.

Cluster

See also section "Configuration of a battery bank” on page 25

Nr. in series

The number of batteries in series

1

1-10

Nr. in parallel

The number of batteries in parallel

1

1-24

Confirm
topology

Button to confirm the number of batteries in
series and/or parallel

Event levels

Capacity low

Level below which the Capacity low event
can be triggered

10%

0-100

Cap. very low

Level below which the Cap. very low event
can be triggered

0%

0-100%

Battery full

Level above which the Battery full event can
be triggered

100

0-100%

High
temperature

Internal temperature of the MLI Ultra serves
as an event source

45°C

30-60°C

18

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

Menu

Description

Default

Adjustable
range

Low
temperature

Internal temperature of the MLI Ultra serves
as an event source

5°C

30-60°C

Voltage low

Level below which the Voltage low event
can be triggered

12.5V

25.0V

12.25-12.75V

24.5-25.5V

Volt. low delay

Delay time to trigger the Voltage low event
after the level was reached

10s

1-120s

Last time 100%

Last time fully charged serves as an event
source. To get accurate SoC readings,
regularly charge the battery to 100%.

31 days

7-60 days

Installer

DOD

To optimize the battery cycle life, the Depth
of Discharge (DOD) is set to 80%.

80%

20-100%

CAUTION!

Changing the DoD to 100% will decrease the cycle life.

SOC 0-10V out

Select this option if the auxiliary connector
is used to display the State of Charge.

Test batt safety

Button to test if the battery switches-off
when the 'battery safety'-conditions are met.

Test stop
charge

Button to test if the chargers stop charging
when the 'stop charge'-conditions are met.

Factory settings

Button to reset the MLI Ultra to its default settings

Events tab

With MasterBus a device can be programmed to initiate an action at another connected device that
supports MasterBus. This is very helpful in automation of your system and is done by means of
event-based commands.

In the Events tab you can program the MLI Ultra to act as an event source. Events which occur
during the operation of the MLI Ultra will then trigger actions from other devices.

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

19

Field

Description

Value

Event x source

Select an event that triggers an action, for example
Relay open.

See Event
source list

Event x target

Select the device that should act, for example the
charger.

Selectable
targets are
device
dependent

Event x command

Select the parameter that must be changed on the
target device, for example No connection.

See command
list of the
selected
device

Event x data

Data translates the input into an output.

• On: status changes to On at first input signal.

• Off: status changes to Off at first input signal.

• Copy: status follows input signal.

• Copy invert: status follows opposite of input.

• Toggle: status changes at 1st signal and back at the

2nd.

Off, On, Copy,
Copy Invert,
Toggle

On

Input

Off

Copy

Toggle

Copy

invert

20

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

Events sources

Event source

Condition

Comments

Disabled

(no event programmed)

Battery Safety

Battery Safety event occurred and the
safety relay is triggered to disconnect
the battery from loads and charger.

See page 33 for what to do if the
battery was switched-off.

Stop charge

Battery voltage > 14.5V/29V (12V/24V
battery), or voltage or temperature of
one of the individual cells is too high.

Strongly recommended event!
Charging

Battery charging current > 1A

Indicates that the battery is being
charged

Capacity low

State of Charge < Capacity low

See Configuration tab - Event levels
for adjustment of the threshold level

Capacity very
low

State of Charge < Capacity very low

See Configuration tab - Event levels
for adjustment of the threshold level
See the related step of the
installation procedure.

Battery full

State of Charge > Battery full.

See Configuration tab - Event levels
for adjustment of the threshold level

Battery > 20%

State of Charge > 19.5 %

Can be used to control the LEDs on
a MasterBus display for example

Battery > 40%

State of Charge > 39.5 %

Battery > 60%

State of Charge > 59.5 %

Battery > 80%

State of Charge > 79.5 %

Battery 100%

State of Charge > 99.5 %

High
temperature

Internal temperature of the MLI Ultra
is too high

See Configuration tab - Event levels
for adjustment of the threshold level

Low
temperature

Internal temperature of the MLI Ultra
is too low

See Configuration tab - Event levels
for adjustment of the threshold level

Voltage low

Battery or cell voltage is too low.

See Configuration tab - Event levels
for adjustment of the threshold level

Last time 100%

Last time the MLI Ultra was fully
charged

See Configuration tab - Event levels
for adjustment of the threshold level

Switch open

Switch open event occurred

Switch close

Switch close event occurred

Over current

Battery over current event occurred

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

21

Event commands

When the MLI Ultra 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 MLI Ultra.

Event command

Meaning

Switch close

The battery switch will be closed.

Switch open

The battery switch will be opened.

Aux. relay close

Closure of relay wire pair 4&5 of the auxiliary cable.

Aux. relay open

Opening of relay wire pair 4&5 of the auxiliary cable.

Heater on

Turn on the heater of the MLI Ultra (provided that the temperature of the MLI
Ultra is below 0°C [32°F]).

Stop Charge event

Before the battery reaches the limits of the operating specifications, the Stop Charge event is
triggered. When configured, this event forces the Mastervolt charger to switch off and resume after
10 minutes. The settings depend on the used charger because different chargers have different

state options. Check the manual of the used charger for how to switch the charging state.

WARNING!
If multiple charging devices are used to charge the battery (for instance both an AC

powered charger and an alternator) then the Stop charge event must be configured for
each charging device. In case of a battery bank, this must be done for each battery.

Stop charge can also be selected by setting DIP switch 3 ON. In this case, all connected Mastervolt
chargers will stop charging when a 'Stop Charge'-condition is met. If a Mastervolt charger is added
to the MasterBus network later in time, the Stop Charge event will automatically be configured for
the new charger. This automatic configuring stops when DIP switch 3 is switched to OFF. However,
this does not clear the existing Stop Charge events!

Examples of Stop charge events:

Event # source

Event # target

Event # command

Event # data

Stop charge

Alpha Pro III

Suspend charging

Copy

Stop charge

ChargeMaster

State

Copy invert

Stop charge

ChargeMaster Plus

Suspend charging

Copy

Stop charge

CombiMaster

Charger

Copy invert

Stop charge

Digital AC 1x6A

Activate

Copy invert

22

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

Event # source

Event # target

Event # command

Event # data

Stop charge

Mac Plus

Standby

Copy

Stop charge

Mass charger

On/Standby

Copy invert

Stop charge

Mass Combi Pro/Ultra

Charger

Copy invert

Stop charge

Multipurpose Contact Output

Activate

Copy

Stop charge

SCM-60 MPPT

On/Off

Copy invert

Configuration in a CZone network

Either do the configuration while connected to the network or use a prepared configuration file (.zcf).
Ensure that a Dipswitch is assigned.

For detailed information on the configuration, please refer to the CZone® Configuration
Tool Instruction manual, and section Configuration in a MasterBus network on page 15,
which describes the parameters as shown in MasterAdjust.

Precondition: This section assumes that a CZone system is already configured and the CZone
Configuration Tool is open.

1. In the CZone Configuration Tool, from the Modules tab, click the Add button.

2. Enter an understandable Module Name.

3. From the Module Type drop-down list, select Battery (BAT).

4. 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.

5. From the Battery Type drop-down list, select the required model.

6. Option: click the Advanced Settings button to configure advanced options.

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

8. To optimize the battery cycle life, the Depth of Discharge Remaining (DoD) is set to 80%.

CAUTION!

Changing the DoD to 100% will decrease the cycle life.

9. Tick Show Battery Temperature to enable temperature monitoring.

10. Click OK to return to the Module Modification window and then click the Alarm/Switch

Settings button.

11. Set the required alarm levels and Alarm Severities.

Battery level 1, 2 and 3 can be used for State of Charge switching.

12. Click OK to close the Battery Alarm/Switch Settings window.

13. Click OK to close the Module Modification window.

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

23

The following steps configure the safety behavior. For example, a Stop Charge switch that stops a
generator and/or battery charger. Or a Battery safety switch that pauses the charging process of an
alternator.

Note: This must be done for all MLI Ultra units and for all charging devices.

14. Click on the Circuits tab and Add a new circuit (bottom left).

15. Enter the Circuit Name (e.g. Stop Charge or Battery Safety) and click OK.

16. Click the Add button in the Circuit Control panel.

17. From the Control Interface drop-down list, select the required MLI Ultra unit.

18. From the Control Input drop-down list, select Stop Charge.

19. Click OK.

Return to step 16 until all MLI Ultra units have this switch configured.

20. Click the Add button in the Circuit Loads panel.

21. From the Load drop-down list, select the required charger.

22. Set the State to Off.

23. Click the Timer/Advanced Settings button.

24. 'Stop Charge' circuit switch only: from the Control Type drop-down list, select Set Limit and

click OK.

25. Click OK to close the Circuit Load Configuration window.

Optionally, return to step 20 to do this for all chargers.

26. Return to step 14 to configure more circuits.

27. Write the configuration to the network to use the new configuration.

24

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

6. BUILDING A BATTERY BANK

The MLI Ultra supports 12V, 24V, 36V and 48V systems.

Requirements:

• Only create battery banks with batteries of the same type and capacity.

• The batteries have the same product code and software version. Do not mix with other models.

• Make sure that all batteries are fully charged before creating a battery bank to ensure balancing

is optimized.

• Use properly sized fuses and wiring.

• Keep the cables between the batteries as short as possible.

• All battery-to-busbar cables should be of the same length.

• Install the batteries as close as possible to the charger.

• Mastervolt recommends one charger for batteries that are connected in series.

• It is best practice to label the batteries (e.g. Primary, Replica1, Replica2).

Series and parallel connections

Note: in the following drawing, the fuses are not depicted. Always use properly sized fuses in the

positive cables of each battery.

2 x 12V parallel = 12V / 200Ah
2 x 24V parallel = 24V / 100Ah

2 x 12V series = 24V / 100Ah
2 x 24V series = 48V / 50Ah

3 x 12V parallel = 12V / 300Ah
3 x 24V parallel = 24V / 150Ah

3 x 12V series = 36V / 100Ah

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

25

4 x 12V parallel = 12V / 400Ah
4 x 24V parallel = 24V / 200Ah

2 x 24V series/parallel = 48V / 100Ah

Figure 10: Simplified diagram for battery bank DC connections

Configuration of a battery bank

Several batteries in series and/or parallel is called a cluster. A cluster can contain up to 24 devices
in total (up to 48V). One MLI Ultra (it does not matter which one) is the Primary unit, the others are
called replica units.

There are two ways to configure a cluster: using DIP switches or using a configuration tool. In a
MasterBus network, a series OR a parallel connection can be configured with DIP switches. A
combination of series and parallel connections must always be configured with a configuration tool,
either MasterAdjust or the CZone Configuration Tool.

Using DIP switches (MasterBus only)

All replica units must have DIP switches 4, 5 and 6 in this position: 001. Their behavior is
determined by the setting of the Primary unit. DIP switches cannot be used for series/parallel
combinations. See section "How to change the DIP switch settings" on page 15 for how to access
the DIP switches.

DIP switch

Model MLI 12/1250

4 5 6

Replica unit

0 0 1

Primary unit 12V system (all batteries in parallel)

0 1 0

Primary unit 24V system (2x batteries in series)

0 1 1

Primary unit 36V system (3x batteries in series)

1 0 0

Primary unit 48V system (4x batteries in series)

1 0 1 DIP switch

Model MLI 24/1250

4 5 6

Replica unit

0 0 1

Primary unit 24V system (all batteries in parallel)

0 1 1

Primary unit 48V system (2x batteries in series)

1 0 1

When all batteries are connected, the Primary unit will check the configuration.

26

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

If the cluster is incomplete or incorrect, LED B keeps blinking 3 times. Possible causes:

• Too many replica units

• Too many primary units

• Replica unit missing

• Primary unit missing

• Incorrect system voltage (e.g. 24V model set as 36V system)

Examples:

3 x 12V parallel (12V system)

Primary

Replica1

Replica2

3 x 12V series (36V system)

Primary

Replica1

Replica2

PRIM

REPL1

REPL2

PRIM

REPL1

REPL2

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

27

Using MasterAdjust

When all batteries are connected to MasterBus, open MasterAdjust. The MLI Ultra will be
recognized by the MasterBus network automatically.

1. Right-click USB:MasterBus… and select Login.

2. Select Installer and enter the installer code.

3. Select the MLI Ultra that will act as Primary and go to the

Configuration tab.

4. Enter the number of batteries in the # series (S) field.

If there are no batteries in series, enter 1.

5. Enter the number of batteries in parallel in the # parallel (P) field.

If there are no batteries in parallel, enter 1.

6. Click the Confirm topology button.

Notice the status of the cluster topology. It can be:

- Approved;

- Needs approval: the topology was not confirmed;

- Not activated: the topology still requires activation;

- Too many devices/Double device/Incomplete/Missing self: the
proposed topology is not possible or other units need to be
selected.

After confirmation, the cluster topology is defined and fields to
select the other units will appear.

7. In the S01 field, the Cluster Primary battery will be shown.

8. In the following fields, select the other replica batteries.

9. Click the Activate button.

Now, each battery will show its individual data in the monitoring
tab while the Primary battery will show both the individual data
and the data of the cluster.

Activation will fail if the battery is already in another cluster.

To access the individual batteries, unfold the cluster (i.e. click the plus sign) in the left panel of
MasterAdjust.

To identify the Primary battery, go to the configuration page of one of the batteries.
To remove a battery from a cluster, click the Detach button on the Configuration tab of the battery in

question.
To breakdown a cluster, in the configuration of the Primary battery: set the cluster to 1 (series) by 1

(parallel) and click the Confirm topology button.

28

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

Using CZone Configuration Tool

Preconditions: - a CZone system is already configured, including all batteries;

- the CZone Configuration Tool opened the required configuration file.

1. In the CZone Configuration Tool, in the Modules tab, double-click the MLI Ultra that will act as

Primary battery.

2. The Module Modifications window appears. Click the Advanced Settings button.

3. From the Cluster Type drop-down list, select Cluster Primary.

4. Cluster DC Instance is an NMEA2000 instance that is used to differentiate between
multiple monitoring sources.

5. Enter a Cluster Name.

6. Click the Configure Topology button.

The Configured Battery Cluster Topology window appears.

7. Enter the number of batteries in series (S). If there are no batteries in series, enter 1.

8. Enter the number of batteries in parallel (P). If there are no batteries in parallel, enter 1.

9. To activate voltage balancing of all cells in series, select ON from the Series Balancing
drop-down list.

10. Click the OK button to return to the Advanced Settings window.

11. Click the OK button to return to the Module Modifications window and then click the
Alarm/Switch Settings button.

12. The Battery Alarm/Switch Settings window appears. To copy these settings from the Primary
battery to all secondary batteries, tick Apply to cluster.

13. Keep clicking OK until all dialog windows have disappeared.

14. Write the configuration to the network to use the new configuration.

To identify the Primary battery, go to the Meters tab. The battery with two DC instances is the Primary
battery.

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

29

7. STORAGE AND CARE

If necessary, use a soft clean cloth to clean the MLI Ultra. Never use any liquids or acids.
The battery should be stored in a dry and well-ventilated environment. The rate of self-discharge is

less than 3% per month. High or low ambient temperature affects the self-discharge rate of the
batteries and natural aging.

If the battery will not be used for a period exceeding 3 months, we advise the following:

• If external AC power is available switch off all loads and switch on the charger. Apply a float
voltage as specified in the following table.

Model

Float voltage setting

12V 13.5V

24V 27.0V

• If no external AC power is available:

- Charge the battery to > 80% of its capacity before storage.

- Long press the Battery switch-button to open the safety relay, see page 7.

- Make sure MasterBus powering is not set to "Always on" (see Configuration tab in

MasterAdjust).

CAUTION!

In this setup the batteries can be kept at least 6 months without maintenance.
However, it is highly recommended to charge the battery to over 80% of its capacity
every 100 days.

30

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

8. TROUBLESHOOTING

To protect it from high/low temperature, high/low cell voltage, and over-current, the MLI Ultra
12/1250, 24/1250 automatically opens a built-in relay to disconnects it from the outside environment
if thresholds are met. See chapter "SPECIFICATIONS" for the thresholds.

To close the safety relay, press the Battery switch-button.

Failure

Possible cause

What to do

No DC power
available

A fuse has blown

Check all fuses and replace if necessary

A cable or cable connection is
defective

Check all cables and their connections.
Replace if necessary.

Crossing the threshold has
triggered the safety relay.

Although the MLI Ultra is protected against
too deep discharges, it will self-discharge
during storage. If the MLI Ultra is deeply
discharged, it will start the self-diagnosis to
determine if it can or cannot be charged
normally. If it cannot be charged normally
and LED A is on, contact your Mastervolt
dealer.

Battery is switched-off (switch is
open)

More than three auto switch-on attempts
within 15 minutes will lead to a 15 minutes
‘cool off’ period. More than nine auto switch­on attempts within 60 minutes will stop the
attempts. To re-enable auto switch-on, long
press (for five seconds) the Battery
switch-button.

If the battery was switched-off manually,
long press (for five seconds) the Battery
switch-button to switch-on again.

MasterBus
display shows
no MLI Ultra

The MasterView Easy has been
configured to display selected
devices only.

Check the option All devices or select the
MLI Ultra to be displayed.
Error in the wiring.

Check the MasterBus cables.

No terminating device placed at
the ends of the network.

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

MasterBus network is
configured as a ring network.

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

Battery is depleted.

Charge the battery.

Over-current
alarm

Too heavy load on the battery.

Reduce load immediately.

LED A is red
on

An unrecoverable error
occurred.

Contact your Mastervolt dealer.

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

31

LED B is
yellow
blinking

One short blink, long pause:
Low State of Charge

Charge the battery.

Two short blinks, long pause:
CZone identification in progress

No action required.

Three short blinks, long pause:
auto cluster configuration error

Check the DIP switch settings. See section
"Using DIP switches”on page 25.

Four short blinks, long pause:
auto recovery initiated

Wait for the auto recovery procedure to
complete.

Steady blinking: firmware
update in progress

No action required.

32

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

9. SPECIFICATIONS

Technical specifications

MLI Ultra 12/1250

MLI Ultra 24/1250

Part number

66011250

66021250

Electrical

Nominal capacity (Cn)

100 Ah

50 Ah

Nominal energy

1250 Wh

1250 Wh

Nominal voltage

12 V

24 V

Self-discharge

Less than 3% per month

Charging/discharging

Charge method

3-step+ (aka IUoUo)

Bulk/absorption (max charge)
voltage

14.25 V

28.5 V
Float voltage (end of charge)

13.5 V

27.0 V

Recommended charge current

50A (0.5C)

25A (0.5C)

Max continuous charge current

100A (1C)

50A (1C)

Max. continuous discharge current

200A (2C)**

100A (2C)

Max. discharge current (peak 10s)

500A (5C)

250A (5C)

Discharge cut-off voltage
(> 0ºC [32°F], <1C)

10V

20V

Mechanical

BCI Group Size

Group 31 ((footprint fits in group 49)

Length (L)

330 mm [13"]

Width (W)

173 mm [6.8"]

Height (H)

210 mm [8.3"] excl. terminals and stud fuse, 228 mm [9"] incl.
terminals

Weight

15 kg [33 lbs]

Protection degree

IP65

Chemistry

LiFePO4

Case material

Plastic

Temperature

Operating temperature

–20 to 50ºC [–4 to 122ºF] *

Nominal operating temp.

25ºC / 77ºF

Storage temperature

–20 to 55ºC [ –13 to 131ºF]

Relative humidity

10 – 95% relative humidity, none condensing

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

33

General

Approvals

CE, E-mark (pending), FCC (pending), UN38.3
UL1642 (cellspack)

Cycle life

3000 cycles at 80% Depth of Discharge

Protection degree

IP65

Parallel configuration

Yes

Series configuration

Yes, up to 48V

Balancing mechanism

Passive

Integrated BMS

Yes

Integrated fuse

No

Integrated disconnect (safety)
switch

Yes
MasterBus connectivity

Yes

Powering capabilities for
MasterBus

Yes
CZone

Yes

* Charging at temperatures below -5ºC / 23ºF may result in battery not accepting charge current.

Temperatures below 5ºC / 41ºF and above 25ºC / 77ºF may affect lifetime and cycle life.

** Due to thermal protection, this high discharge current can be used for 5 minutes at or above an ambient

temperature of 25ºC [77ºF].

Battery switch – automatic behavior

CAUSE FOR AUTO
SWITCH-OFF

CONDITIONS (for at least 30 seconds) FOR AUTO SWITCH-ON

• Cell over-voltage

• Cell under-voltage

• Battery over-current

• Cell over-temperature

Cell voltages and temperatures are within safe operating range

• Low SoC

Charger is connected

• Extreme over­temperature (> 85°C /
185ºF)

• BMS failure

 Battery switched-off permanently

Notes: - If DIP switch 6 is ON, then the auto switch-on feature is disabled.

- When the battery is switched-off manually, it also needs to be switched-on manually.

34

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

Characteristics

Battery discharge characteristics and battery capacity at ambient temperature 25ºC/77ºF

• 12/1250

Battery voltage (V)

1C

0.5C

0.3C

Remaining battery capacity (Ah)

• 24/1250

Battery voltage (V)

1C

0.5C

0.3C

Remaining battery capacity (Ah)

Capacity retention over lifetime at ambient temperature 25ºC/77ºF

Capacity retention (%)

100% DoD

80% DoD

50% DoD

Number of cycles

MLI Ultra 12/1250, 24/1250 – User and Installation Manual

35

Capacity retention at different cell temperatures

Capacity retention (%)

Available

capacity

Cell temperature (°C)*

* Cell temperatures are not necessarily equal to the ambient temperature of the battery!

Cycle life retention at different ambient temperatures

Cycle

life retention (%)

1C

Ambient temperature (°C)

Self-discharge in reflection to the storage temperature

Capacity (%)

20°C / 140°F
25°C / 86°F
30°C / 77°F
40°C / 68°F

Storage in months*

* Provided that MasterBus powering is off and there is no communication to the BMS.

Europe, Middle East & Africa

Customer Service

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

Technical Support

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

Location & Shipping

Advanced Systems Group EMEA
Snijdersbergweg 93
1105 AN Amsterdam
The Netherlands

Americas & Caribbean

Customer Service

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

Technical Support

T: [phone], option 2
E: [e-mail]

Location & Shipping

Power Products, LLC
N85 W12545 Westbrook Crossing
Menomonee Falls, Wisconsin 53051
United States

Asia Pacific

Customer Service

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

Technical Support

T: [phone], option 3
E: [e-mail]

Location & Shipping

BEP Marine
42 Apollo Drive
Rosedale, Auckland 0632
New Zealand

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Mastervolt. All rights reserved.

Reproduction, transfer, distribution or storage of part or

all of the contents in this

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