Mastervolt CombiMaster 120V Series Operating manual

COMBIMASTER
120V Series: 12/1500-60,
12/2000-100, 12/3000-160, 24/2000-60, 24/3000-70,
12/3500-200, 24/3500-100, 24/4500-120, 48/5000-70
INVERTER CHARGER COMBINATION
WITH AC–IN SUPPORT
USER AND INSTALLATION MANUAL
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2
CombiMaster 120V Series
– User and Installation Manual
TABLE OF CONTENTS
1SAFETY INSTRUCTIONS ............................................ 3
1.1 General ................................................... 3
1.2 Warnings regarding the use of batteries .. 4
1.3 Location................................................... 5
1.4 Connections ............................................ 5
1.5 Warning regarding life support
applications ............................................. 5
2GENERAL INFORMATION .......................................... 6
2.1 Liability .................................................... 6
2.2 Warranty.................................................. 6
2.3 Identification label.................................... 6
2.4 Correct disposal of this product ............... 6
3PRODUCT DESCRIPTION........................................... 7
3.1 Overview of the connections.................... 7
3.1.1 Models 1500W, 2000W, 3000W............ 7
3.1.2 Models 3500W, 4500W, 5000W............ 8
3.2 Operating modes..................................... 8
3.3 Protection .............................................. 10
4INSTALLATION.......................................................... 11
4.1 Unpacking ............................................. 11
4.2 Location................................................. 11
4.3 Batteries ................................................ 12
4.4 Connection examples ............................ 13
4.4.1 Models 1500W, 2000W, 3000W.......... 13
4.4.2 Models 3500W, 4500W, 5000W.......... 14
4.5 Wiring.................................................... 15
4.5.1 DC wiring ............................................ 15
4.5.2 AC wiring............................................. 16
4.5.3 AC safety grounding............................ 17
4.5.4 Network wiring (CZone/MasterBus)..... 18
4.6 Tools and materials needed .................. 19
4.7 Installation step-by-step......................... 20
4.8 Accessories connector (dry contacts) .... 23
4.8.1 Remote switch..................................... 24
4.8.2 Output ................................................. 24
5SETTINGS .................................................................. 25
5.1 DIP switch settings ................................ 25
5.2 MasterBus configuration........................ 26
5.2.1 Monitoring tab ..................................... 26
5.2.2 Alarms tab........................................... 28
5.2.3 History tab........................................... 28
5.2.4 Configuration tab................................. 28
5.2.5 Events tab – System automation......... 31
5.3 CZone configuration .............................. 32
6OPERATION...............................................................34
6.1 Switching on / charge only .....................34
6.2 Status LEDs...........................................34
6.3 Remote control.......................................35
6.4 3-step+ charge process..........................35
6.5 Temperature compensated charging......36
6.6 Reset the thermal breaker after an
overload .................................................36
6.7 Maintenance ..........................................37
6.7.1 Decommissioning ................................37
6.7.2 Storage and transportation ..................37
7PARALLEL AND SPLIT-PHASE SYSTEMS..............38
7.1 General information................................38
7.2 Materials needed ...................................39
7.3 Preparations ..........................................39
7.4 DC wiring ...............................................40
7.5 AC wiring ...............................................41
7.5.1 AC wiring of single-phase parallel
units.....................................................42
7.5.2 AC wiring of split-phase units (one unit
for each phase)....................................43
7.5.3 AC wiring of split-phase (two parallel
units for each phase) ...........................45
7.6 Network wiring .......................................46
7.6.1 Preparation ..........................................46
7.6.2 Network wiring of single-phase parallel
units.....................................................47
7.6.3 Network wiring of split-phase units.......47
7.6.4 Network wiring of two units in split-phase
with two units in parallel.......................48
7.7 Configuration and initial start-up.............48
7.7.1 DIP switches (for a single-phase parallel
configuration in a basic MasterBus
system)................................................49
7.7.2 MasterAdjust........................................50
7.7.3 CZone Configuration Tool....................51
7.8 Breaking down a cluster.........................53
8TROUBLESHOOTING................................................ 54
9TECHNICAL DATA.....................................................56
9.1 Inverter specifications ............................56
9.2 Charger specifications............................57
9.3 Transfer system specifications ...............59
9.4 Miscellaneous ........................................60
9.5 CZone specifications..............................60
9.6 Characteristics .......................................61
9.7 Dimensions ............................................62

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CombiMaster 120V Series
– User and Installation Manual
1 SAFETY INSTRUCTIONS
IMPORTANT SAFETY INSTRUCTIONS
SAVE THESE INSTRUCTIONS
1.1 General
1. This manual contains important safety and operating instructions for the following models:
Model
Product code
CombiMaster 12V/1500W-60A 120V 35511500
CombiMaster 12V/2000W-100A 120V
35512000
CombiMaster 12V/3000W-160A 120V 35513000
CombiMaster 12V/3500W-200A 120V
35513500
CombiMaster 24V/2000W-60A 120V 35522000
CombiMaster 24V/3000W-70A 120V
35523000
CombiMaster 24V/3500W-100A 120V 35523500
CombiMaster 24V/4500W-120A-HT 120V
35524500
CombiMaster 48V/5000W-70A-HT 120V 35545000
These models are further referred to as “CombiMaster Inverter/Charger“.
2. CAUTION – To reduce risk of injury, the CombiMaster Inverter/Charger may only be used for
charging Lead-acid type (flooded, Gel, AGM) or Mastervolt Lithium-Ion rechargeable batteries and
the supply of loads attached to these batteries, in permanent systems. Other types of batteries may
burst causing personal injury and damage.
3. Do not expose the CombiMaster Inverter/Charger to rain, snow, spray, moisture, excessive
pollution, aggressive environments, ammonia, salt or condensing circumstances.
4. Use of an attachment not recommended or sold by Mastervolt may result in a risk of fire, electric
shock, or injury to persons.
5. Except for making the electrical connections, the CombiMaster Inverter/Charger may not be
opened. There are no serviceable parts inside the casing. Do not disassemble the CombiMaster
Inverter/Charger; take it to qualified service personnel when service or repair is required. Incorrect
reassembly may result in a risk of electric shock or fire.
6. To reduce risk of electric shock, disconnect the CombiMaster Inverter/Charger 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.
7. The CombiMaster Inverter/Charger 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.
8. In case of fire, you must use the fire extinguisher which is appropriate for electrical equipment.
9. CAUTION – Risk of Electric Shock. Both AC and DC voltage sources are terminated inside this
equipment. Each circuit must be individually disconnected before servicing.
10. CAUTION – Risk of electric shock from energy stored in capacitor. Do not remove cover until 5
minutes after disconnecting all sources of supply.

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CombiMaster 120V Series
– User and Installation Manual
1.2 Warnings regarding the use of batteries
1. WARNING – RISK OF EXPLOSIVE GASES
i. WORKING IN VICINITY OF A LEAD-ACID BATTERY IS DANGEROUS. BATTERIES
GENERATE EXPLOSIVE GASES DURING NORMAL BATTERY OPERATION. FOR
THIS REASON, IT IS OF UTMOST IMPORTANCE THAT EACH TIME BEFORE
SERVICING THE COMBIMASTER INVERTER/CHARGER IN THE VICINITY OF THE
BATTERY, YOU READ THIS MANUAL AND FOLLOW THE INSTRUCTIONS
EXACTLY.
ii. To reduce risk of battery explosion, follow these instructions and those published by battery
manufacturer and manufacturer of any unit you intend to use in vicinity of battery. Review
cautionary marking on these products and on engine.
2. PERSONAL PRECAUTIONS
i. Someone should be within range of your voice or close enough to come to your aid when you
work near a lead-acid battery.
ii. Have plenty of fresh water and soap nearby in case battery acid contacts skin, clothing, or eyes.
iii. Wear complete eye protection and clothing protection. Avoid touching eyes while working near
battery.
iv. 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 min and get medical attention
immediately.
v. NEVER smoke or allow a spark or flame in vicinity of battery or engine.
vi. Do not short circuit battery! Be extra cautious to reduce risk of dropping a metal tool onto
battery. It might spark or short-circuit battery or other electrical part that may cause explosion.
vii. Remove personal metal items such as rings, bracelets, necklaces, and watches when working
with batteries. A battery can produce a short-circuit current high enough to weld a ring or the like
to metal, causing a severe burn.
viii. NEVER charge a frozen battery.
ix. If necessary, to remove battery from a vessel or vehicle, always remove grounded terminal from
battery first. Make sure all accessories in the vessels or vehicle are off, so as not to cause an
arc.
x. Be sure that the area around battery is well ventilated.
xi. Clean battery terminals. Be careful to keep corrosion from coming in contact with eyes.
xii. Study all battery manufacturer’s specific precautions such as removing or not removing cell caps
while charging and recommended rates of charge.
xiii. Add distilled water in each cell until battery acid reaches level specified by battery manufacturer.
This helps purge excessive gas from cells. Do not overfill. For a battery without cell caps (e.g.
AGM, Gel or Li-ion batteries), carefully follow manufacturer’s recharging instructions.
xiv. A battery is 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.

CombiMaster 120V Series –
User and Installation Manual
5
1.3 Location
1. COMBIMASTER INVERTER/ CHARGER LOCATION
i. Locate the CombiMaster Inverter/Charger away from battery in a separate, well-ventilated
compartment.*
ii. Never place the CombiMaster Inverter/Charger directly above battery; gases from battery will
corrode and damage the CombiMaster Inverter/Charger.*
iii. Never allow battery acid to drip on the CombiMaster Inverter/Charger when reading gravity or
filling battery.*
iv. Do not operate the CombiMaster Inverter/Charger in a closed-in area or restrict ventilation in any
way. To reduce risk of fire hazard, do not cover or obstruct the ventilation openings.
* This restriction does not apply to Li-ion batteries.
1.4 Connections
1. DC CONNECTION PRECAUTIONS
i. Connect and disconnect DC output connections only after setting any switches of the
CombiMaster Inverter/Charger to off position and removing AC connections or opening AC
disconnect switch.
ii. Short circuiting or reversing polarity will lead to serious damage to batteries, the CombiMaster
Inverter/Charger, wiring as well as accessories. Fuses cannot prevent damage caused by
reversed polarity and the warranty will be void.
2. EXTERNAL CONNECTIONS TO CombiMaster Inverter/Charger SHALL COMPLY WITH THE
UNITED STATES COAST GUARD ELECTRICAL REGULATIONS (33CFR183, SUB PART I).
3. GROUNDING INSTRUCTIONS – The CombiMaster Inverter/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 unit. Connections
to the CombiMaster Inverter/Charger should comply with all local codes and ordinances.
1.5 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.

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CombiMaster 120V Series
– User and Installation Manual
2 GENERAL INFORMATION
2.1 Liability
Mastervolt can accept no liability for:
•Consequential damage resulting from the use of the CombiMaster Inverter/Charger.
•Possible errors in the included manual and the consequences of these.
•Use that is inconsistent with the purpose of the product.
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.
2.2 Warranty
The Mastervolt product warranty covers the CombiMaster 120V Series 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.
2.3 Identification label
The following picture is only an example!
Part number
Serial number
L821A0001,
device version
"A".
Important information required for service or
maintenance can be derived from the
identification label. The identification label is
located at the right-hand side of the
CombiMaster Inverter/Charger
CAUTION!
Never remove the identification
label. This will void the warranty
Figure 1: Example of an identification label
2.4 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.

CombiMaster 120V Series –
User and Installation Manual
7
3 PRODUCT DESCRIPTION
The CombiMaster Inverter/Charger is a battery charger, inverter and AC transfer system in one
compact case.
3.1 Overview of the connections
3.1.1 Models 1500W, 2000W, 3000W
Front side with open connection compartment
Bottom side
Figure 2. Connections for models with product code: 35511500, 35512000, 35513000, 35522000,
35523000.
1 Neutral-ground bonding
2 AC input
3 Status LEDs
4 M8 Positive battery terminal
5 M8 Negative battery terminal
6 AC output
7 DIP switches
8 Resettable thermal breaker (30A)
9 "On/Charge only"-switch
10 5/16" Ground stud
11 CZone/MasterBus connection
12 Accessories connector
13 Temperature sensor connection

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CombiMaster 120V Series
– User and Installation Manual
3.1.2 Models 3500W, 4500W, 5000W
Front side with open connection compartment
Bottom side
Figure 3. Connections for models with product code: 35513500, 35523500, 35524500, 35545000.
1 Neutral-ground bonding
2 AC input
3 Status LEDs
4 5/16" Positive battery terminal
5 5/16" Negative battery terminal
6 AC output
7 DIP switches
8 Resettable thermal breaker (50A)
9 "On/Charge only"-switch
10 5/16" Ground stud
11 CZone/MasterBus connection
12 Accessories connector
13 Temperature sensor connection
14 Current sharing (parallel unit configuration)
15 Cluster communication ports (multi-unit
configuration)
For information on multi-unit configurations, see chapter 7.
3.2 Operating modes
•
Inverter mode: When there is no external AC
power available, the inverter provides AC power
on the AC output. If energy saving mode is
enabled, battery power consumption will be
reduced when there is no load on AC OUT.
Please note that some electronic loads such as
wifi routers, satellite receivers, or digital clocks
are most likely not to work in this mode.
•Charger mode: When external AC power is
available on the AC input, the battery will be
charged and the AC output is supplied by the
external power.

CombiMaster 120V Series –
User and Installation Manual
9
•DC power supply mode: During an installation
procedure, it may be desirable to test onboard
systems before connecting a battery bank. To do
this, start the CombiMaster Inverter/Charger with
no load connected. Wait for one minute and then
connect a low power DC load. In small steps,
25A max, more loads can be switched-in
sequentially. Do not exceed 50A to prevent
unstable power supply.
•Power sharing mode: The CombiMaster Inverter/Charger automatically reduces its battery charger
output when the load connected to AC OUT increases while the available power at AC IN is limited.
This avoids the external AC circuit breaker from tripping. The power sharing level, i.e. AC IN Limit
setting (adjustable from an optional display), should match the value of the external circuit breaker.
Load on AC OUT < AC IN Limit
Load on AC OUT ≥ AC IN Limit
•AC input support mode: If the demand for AC power
still increases, the AC input circuit breaker may still
trip if nothing is done. This problem can be solved by
the AC IN Support mode. If the total demand for
power exceeds the max external power supply, power
can be added to AC OUT by means of the inverter.
This means that the inverter adds power from the
batteries, in parallel with the external power source.
CAUTION!
The continuous load connected to AC OUT should never exceed
•40A for models 1500W, 2000W, 3000W,
•85A models 3500W, 4500W, 5000W.
Exceeding the max allowable output current may damage the product.
Note: Depending on national or local regulations regarding AC sources operating in parallel with the
AC grid, AC IN support mode may not be allowed! Familiarize yourself with local regulations on
this issue. AC power from the inverter will never be fed back into the AC grid.
See chapter 5 on page 25 for the required settings for all modes.

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CombiMaster 120V Series
– User and Installation Manual
3.3 Protection
•Overload or short circuit: while in the inverter mode, the CombiMaster Inverter/Charger will shut
down within 5 seconds of 200% overload or after 10 seconds 150%.
•Transfer switch overload: the transfer switch of the CombiMaster Inverter/Charger is protected
against overload and short circuit. When the current through the transfer switch of the CombiMaster
Inverter/Charger is exceeding what it is rated for,
- 30A for models 1500W, 2000W, 3000W, or
- 50A for models 3500W, 4500W, 5000W, then
the thermal breaker (item 8 on page 7) will disconnect the AC input.
•High temperature: if the temperature of the CombiMaster Inverter/Charger is too high, the inverter
shuts down or the charger will reduce power. This will trigger the status LEDs and optionally a
remote alarm. High temperature is most likely caused by heavy loads operating for a longer period,
high ambient temperature or disrupted air flow (dust or too little space). When the temperature
returns to normal operating range, the inverter powers up automatically or the charger resumes.
See section 9.6 for details.
•Battery low/high: the CombiMaster Inverter/Charger warns for low or high battery voltages by
triggering status LEDs and CZone/MasterBus alarms.
CAUTION!
The CombiMaster Inverter/Charger is not protected against:
- over voltage on the AC input;
- continuous overload on the AC output.
Make sure AC input is within the range of 90-140VAC and the continuous load connected to
AC OUT never exceeds
•40A for models 1500W, 2000W, 3000W,
•85A for models 3500W, 4500W, 5000W.

CombiMaster 120V Series –
User and Installation Manual
11
4 INSTALLATION
4.1 Unpacking
The delivery includes:
•CombiMaster Inverter/Charger
•1× Temperature sensor with cable and plug
•1× MasterBus terminator
•1× RJ45-M12 Drop cable CZone (1m)
•Mounting bracket
•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 Mastervolt dealer. Check from the identification label (see section 2.3) whether the
battery voltage is the same as the nominal output voltage of the CombiMaster Inverter/Charger (e.g.
24V battery set for a 24V inverter/charger). Also check that the AC output voltage and output power of
the CombiMaster Inverter/Charger complies with your system and loads.
4.2 Location
•The CombiMaster Inverter/Charger is designed for indoor use only.
•Ambient temperature
- models 1500W, 2000W, 3000W, 3500W:
14°F to 140°F [-10°C to 60°C], power derating above 104°F [40°C].
- models 4500W, 5000W:
14°F to 176°F [-10°C to 80°C], power derating above 104°F [40°C].
•Humidity: 5-95% non-condensing
•This device requires a minimum of 4" [100mm] of clearance on every side to ensure safety and
proper ventilation
•If the CombiMaster Inverter/Charger is installed in the immediate vicinity of living areas, take into
account that the fan(s) of the CombiMaster Inverter/Charger can produce noise when operating.
•The CombiMaster Inverter/Charger can be tabletop mounted (IP 21) as well as wall mounted (IP
23).
•The CombiMaster Inverter/Charger complies with FCC Class B notification: This equipment has
been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of
the FCC Rules. These limits are designed to provide reasonable protection against harmful
interference in a residential installation. This equipment generates, uses and can radiate radio
frequency energy and, if not installed and used in accordance with the instructions, may cause
harmful interference to radio communications. However, there is no guarantee that interference will
not occur in a particular installation. If this equipment does cause harmful interference to radio or
television reception, which can be determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one or more of the following measures:
- Reorient or relocate the receiving antenna.
- Increase the separation between the equipment and receiver.
- Connect the equipment into an outlet on a circuit different from that to which the receiver is
connected.
- Consult the dealer or an experienced radio/TV technician for help.
Note: The changes or modifications not expressly approved by the party responsible for compliance
could void the user's authority to operate the equivalent.

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CombiMaster 120V Series
– User and Installation Manual
4.3 Batteries
Model
Recommended battery capacity
Minimum, based on Mastervolt Gel
batteries. If connecting batteries of a
different manufacturer, make sure
the manufacturer's recommendations
are met.
12V/1500W-60A
120−600 Ah
12V/2000W-100A
200−1000 Ah
12V/3000W-160A
320
−
1600 Ah
12V/3500W-200A
400
−
2000 Ah
24V/2000W-60A
120
−
600 Ah
24V/3000W-70A
140
−
700 Ah
24V/3500W-100A
200
−
1000 Ah
24V/4500W-120A-HT
240
−
1200 Ah
48V/5000W-70A-HT
140
−
700 Ah

CombiMaster 120V Series –
User and Installation Manual
13
4.4 Connection examples
These schematics illustrate the general placement of a standalone CombiMaster Inverter/Charger in a
circuit. It is not meant to provide detailed wiring instructions for any particular electrical installation. For
information on multi-unit configurations, see chapter 7.
4.4.1 Models 1500W, 2000W, 3000W
Figure 4: Installation drawing for models with product code: 35511500, 35512000, 35513000,
35522000, 35523000

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CombiMaster 120V Series
– User and Installation Manual
4.4.2 Models 3500W, 4500W, 5000W
Figure 5: Installation drawing for models with product code: 35513500, 35523500, 35524500, 35545000

CombiMaster 120V Series –
User and Installation Manual
15
4.5 Wiring
WARNING!
The wire sizes stated in this manual are only guidelines. Fusing is based on the gauge and
length of the cable, which in turn depend on the load connected to the CombiMaster
Inverter/Charger. Always comply with all local rules and regulations.
WARNING!
Turn off the DC and AC power source during installation. Powered wires can spark when
touching the CombiMaster Inverter/Charger DC or AC terminals.
4.5.1 DC wiring
Always keep your wire runs as short as practical to prevent low voltage shutdowns and to keep the DC
breaker from nuisance tripping (or open fuses) because of increased current draw.
Model
DC cable cross section
Inline fuse
<10ft [3m]
10-16ft [3-5m]
12V/1500W-60A
AWG 1/0 [50 mm2]
AWG 2/0 [70 mm2]
200A
12V/2000W-100A
AWG 2/0 [70 mm2]
AWG 3/0 [95 mm2]
250A
12V/3000W-160A
AWG 3/0 [95 mm2]
AWG 4/0 [120mm2]
350A
12V/3500W-200A
AWG 4/0 [120 mm2]
2 x AWG 2/0 [2 x 70 mm2]
1x 400 or 2x 200A
24V/2000W-60A
AWG 2 [35 mm2]
AWG 1/0 [50 mm2]
130A
24V/3000W-70A
AWG 1/0 [50 mm2]
AWG 2/0 [70 mm2]
200A
24V/3500W-100A
AWG 2/0 [70 mm2]
AWG 3/0 [95 mm2]
250A
24V/4500W-120A-HT
AWG 3/0 [95 mm2]
AWG 4/0 [120 mm2]
300A
48V/5000W-70A-HT
AWG 1/0 [50mm2]
AWG 2/0 [70 mm2]
175A
Note: make sure that the fuse's voltage rating meets the battery voltage. Especially for a 48V system
because most fuses do not exceed 32V.
Use cable lugs on the ends of the wires. These lugs should be crimped with a proper crimping tool.
Recommended wire colors (refer to local rules):
Wire color
Meaning
Connect to:
Red Positive + (POS)
Black or yellow
Negative
– (NEG)
Do not put anything between the battery cable ring lug and the battery post or the inverter’s DC
terminal. When connecting the battery cable to the battery post or inverter DC terminal, the cable
should be placed directly against the inverter terminal or battery post. Incorrectly installed hardware
causes a high resistance connection which could lead to poor inverter/charger performance and may
affect the cable and terminal connections.
Run the 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
cable must be fused and connected to the positive post of the battery bank. Use a fuse that matches
the applied wire gauge and is rated at 125 to 150% of the full load current. The fuse with fuse-holder is
available from your local Mastervolt distributor.
For more information on fuses, consult Blue Sea's Wire, Fuse and Fuse Holder Selection Chart.
[http://assets.bluesea.com/files/resources/reference/20010.pdf ]

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CombiMaster 120V Series
– User and Installation Manual
4.5.2 AC wiring
WARNING!
The ground wire offers protection only if the case of the CombiMaster Inverter/Charger is
connected to the safety ground. Connect the ground terminal (PE / GND) to the hull or the
chassis of the boat or vehicle that this CombiMaster Inverter/Charger is equipped on.
WARNING!
For safety reasons Ground Fault Circuit Interrupters (GFCIs), also known as Residual
Current Devices (RCDs), must be integrated in the AC input and AC output of the
CombiMaster Inverter/Charger. Always comply with all local rules and regulations.
CAUTION!
For the isolation transformer that is used at the AC input, choose a transformer with at least
2x the total inverter power of the units. Too small a transformer causes unstable behavior!
For a safe installation the correct wire cross section must be applied. Don’t use a cross section that is
smaller than indicated. When cables are longer than 10 feet [3m], the size should be increased (one
size over) to compensate for cable losses. Maximum AC breaker size:
Model 12/1500-60, 12/2000-100, 12/3000-160,
24/2000-60, 24/3000-70
12/3500-200, 24/3500-100,
24/4500-120, 48/5000-70
AC input circuit breaker
30A* (12 AWG [4mm
2
] wire)
50A* (8 AWG [10 mm
2
] wire)
AC output circuit breaker 40A (10 AWG [6 mm2] wire) 85A (6 AWG [16 mm2] wire)
* or less when the AC supply is rated for lower value
Recommended wire colors 120VAC single-phase (refer to local rules):
Color
Meaning
Must be connected to
Black Hot or Line L
White Neutral N
Green Ground

CombiMaster 120V Series –
User and Installation Manual
17
4.5.3 AC safety grounding
WARNING!
If installed in a head, galley, machinery space, or on a weather deck, Ground Fault Circuit
Interrupters (GFCIs) of 30mA must be integrated in the AC input and AC output of the
CombiMaster Inverter/Charger.
An Equipment Leakage Circuit Interrupter (ELCI) shall be installed within 10" of the shore
power inlet.
Refer to locally applicable regulations regarding grounding of autonomous power systems.
Neutral to Ground Bonding
To ensure a correct operation of Ground Fault Circuit Interrupters (GFCIs), the AC output Neutral (N)
connects to the Safety Ground (PE) –the so called neutral to ground bonding– when the AC input of the
CombiMaster Inverter/Charger is disconnected from an external AC source. This default setting of the
grounding system works well in most situations. However, depending on national or local regulations,
neutral to ground bonding may not be allowed. In that case, this automatic switching feature must be
disabled.
•Models 1500W, 2000W, 3000W
The selection of enabling/disabling automatic
neutral to ground bonding in inverter mode, is
done by positioning the grounding system
jumper (located on the left side of the
CombiMaster Inverter/Charger).
Default
setting
To disable this
automatic
bonding, move
the jumper to
position X-N.
Bonding
disabled
•Models 3500W, 4500W, 5000W
The selection of enabling/disabling automatic
neutral to ground bonding in inverter mode is
done by positioning the two M3x8 screws
(located on the left side of the CombiMaster
Inverter/Charger, behind a removable plate).
For a multi-unit configuration with single point
neutral to ground bonding, please refer to the
related Technical Bulletin. Technical Bulletins
are published on the portal on the Mastervolt
website.
Default
setting
To disable this
automatic
bonding, move
the upper screw
to the middle.
Bonding
disabled

18
CombiMaster 120V Series
– User and Installation Manual
4.5.4 Network wiring (CZone/MasterBus)
The CombiMaster Inverter/Charger can be connected to a CZone or MasterBus network. For CZone,
use an RJ45 CZone drop cable to connect to the CZone backbone. For MasterBus, use a MasterBus
cable and daisy chain the CombiMaster Inverter/Charger to the other devices. Both networks need a
terminating device on both ends of the network. Do not make ring networks. For more details on
networks, please contact your Mastervolt dealer.
•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 run as possible
to reduce voltage drop.
˗Each device on the CZone network has a unique CZone address; the Dipswitch. This number is
usually assigned automatically during configuration and must match the DIP switch settings on
the CombiMaster Inverter/Charger.
•MasterBus network
Use an RJ45 MasterBus cable (not included) and daisy chain the CombiMaster Inverter/Charger to
the other MasterBus devices, forming a local data network.
Points to consider:
˗Connections between the devices are made by standard MasterBus cables. Mastervolt can
supply these cables.
˗Up to 63 MasterBus devices can be connected together.
˗MasterBus needs a terminating device on both ends of the network.
˗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
˗Do not make ring networks.
˗Do not make T-connections in the network.
CAUTION!
Never connect a non-MasterBus device to the MasterBus network directly! This will
void warranty of all MasterBus devices connected.
For more details on networks, please contact your Mastervolt dealer.

CombiMaster 120V Series –
User and Installation Manual
19
4.6 Tools and materials needed
Make sure you have all the materials you need to install a CombiMaster Inverter/Charger:
•For CZone setup, a tee connector.
•For MasterBus setup, an RJ45 MasterBus cable.
•DC cables to connect the CombiMaster Inverter/Charger to the batteries and common negative. See
section 4.5.1 for specifications.
•DC fuse holder with a DC fuse, to be integrated in the positive DC cable (as per ABYC
recommendations).
•Screws/bolts (Ø ¼" / 6mm) with plugs to mount the CombiMaster Inverter/Charger to a surface. Use
mounting materials which are suited to carry the weight of the CombiMaster Inverter/Charger.
•AC cable to connect the AC input to an AC power source. See section 4.5.2 for specifications.
•Batteries. See section 4.3 for specifications.
•Appropriate and reliable cable terminals, cable lugs, battery terminals and cord end terminals.
We recommend as a minimum tool kit:
•Socket wrench to fix the main DC cables (M8 / 5/16")
•Socket wrench to fix the Safety ground connection (5/16").
•Flat blade screwdriver to fix the screw terminals of the AC wiring.
•Tools to fix the screws / bolts (Ø ¼" / 6mm) with plugs to mount the CombiMaster Inverter/Charger to
a surface.
•Philips screwdriver to open the connection compartment.

20
CombiMaster 120V Series
– User and Installation Manual
4.7 Installation step-by-step
The drawings used in this section are based on the 3000W model. Where necessary, the difference is
indicated.
Step 1. Turn off the electrical power.
Step 2. On a solid surface, mark the holes for the mounting bracket and secure the mounting bracket
to the surface.
Wall
mounted
Tabletop
mounted
Note: Make sure that the mounting surface and material can support the weight of the
CombiMaster Inverter/Charger.
Step 3. Place the CombiMaster Inverter/Charger over the mounting bracket and then downwards
until it snaps into place.
Step 4. Secure the CombiMaster Inverter/Charger to the surface by fastening two screws at the lower
side of the case as well.