Mastervolt AC Master 12/300 Operating manual

AC Master
12/300, 12/500, 24/300, 24/500
PURE SINE WAVE INVERTER
USER AND INSTALLATION MANUAL
1000014304/01
To download this manual in other languages, please
visit our website: www.mastervolt.com

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AC Master
12/300, 12/500, 24/300, 24/500 – User and Installation Manual
Table of contents
1 Safety instructions ........................................................................................................................... 3
2 Liability ............................................................................................................................................ 3
3 Disclaimer ........................................................................................................................................ 3
4 Warranty .......................................................................................................................................... 3
5 Correct disposal of this product........................................................................................................ 3
6 Product description .......................................................................................................................... 4
7 Installation instructions .................................................................................................................... 5
8 Operation ......................................................................................................................................... 8
9 Troubleshooting ............................................................................................................................... 9
10 Specifications ................................................................................................................................ 10

AC Master 12/300, 12/500, 24/300, 24/500 – User and Installation Manual
3
1 Safety instructions
WARNING!
Read the entire manual before using the AC Master. Keep the manual in a secure place.
 Use the AC Master following the instructions and specifications stated in this manual.
 Connections and safety features must be executed according to the locally applicable regulations.
 Operation of the AC Master without proper grounding may lead to hazardous situations!
 Use DC-cables with an appropriate size. Integrate a fuse in the positive wiring and place it nearby
the battery. Refer to the specifications.
 If the positive and negative wires on the DC-input (battery) are exchanged, the AC Master will be
damaged. Damage of this kind is not covered by guarantee. Check whether all connections are
connected correctly before placing the fuse.
 Do not connect the AC-output of the AC Master to an incoming AC source.
 Never connect the AC Master in parallel with any other inverter.
 Never open the housing as high voltages may be present inside!
2 Liability
Mastervolt cannot be held liable for:
 Consequential damage resulting from the use of the AC Master.
 Possible errors in the included manual and the consequences of these.
 Use that is inconsistent with the purpose of the product.
3 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. Consult our most current Terms & Conditions of Sale.
4 Warranty
Mastervolt assures the product warranty of the AC Master during two years after purchase, on the
condition that the product is installed and used according to the instructions in this manual.
Installation or use not according to 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 for labour or shipping are not covered by this warranty.
5 Correct disposal of this product
(Waste Electrical & Electronic Equipment)
This product is designed and manufactured with high quality materials and components,
which can be recycled and reused. When this crossed-out wheeled bin symbol is attached to
a product, it means the product is covered by the European Directive 2012/19/EU.
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.

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AC Master
12/300, 12/500, 24/300, 24/500 – User and Installation Manual
6 Product description
The AC Master is a sine wave inverter. The AC Master converts DC power from the battery into AC
output power.
Identification label
Part number Serial number J821A0001 with device version “A”
Important information
required for service or
maintenance can be
derived from the
identification label.
Never remove this label!
Dimensions in mm [inch]

AC Master 12/300, 12/500, 24/300, 24/500 – User and Installation Manual
5
Connections
1 Main switch
2 DC fuse(s)
3 DC input cables (1.5m)
4 Chassis ground terminal (M6)
5 AC output socket (IEC)
7 Installation instructions
This section provides a step by step instruction of the basic installation of the AC Master.
Step 1. Disconnect power supplies.
Step 2. Switch OFF the AC Master.
PE
L
N
ON
OFF
POWER SAVING

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AC Master
12/300, 12/500, 24/300, 24/500 – User and Installation Manual
Step 3. Select a location to install.
• Install the AC Master in a well-ventilated room protected against rain, snow, spray, vapour, bilge,
moisture and dust.
• Ambient temperature: -20 to 40°C / -4 to 104°F.
• Never use the AC Master at a location where there is danger of gas or dust explosions. Mount
the AC Master vertically with the cables hanging downwards and so that airflow through the
ventilation openings is guaranteed. Mounting the AC Master in another position is possible but
influences the ingress protection degree (IP)!
• No objects are to be located within a distance of 10 cm / 4 inch around the AC Master.
• Do not install the AC Master in the same compartment as the batteries. Do not mount the AC
Master straight above the batteries because of possible corrosive sulphur fumes.
Step 4. Remove the fuse cover and DC fuse(s).
Step 5. Mount the AC Master with four screws to a solid surface.
Step 6. Connect the chassis ground terminal to the central grounding point of the vehicle/ship.

AC Master 12/300, 12/500, 24/300, 24/500 – User and Installation Manual
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Step 7. Connect the battery to the DC input. Do not place the fuse yet!
Step 8. Wire the IEC plug.
See also figure Connections on page 5.
Front view of the IEC C14 male plug
Step 9. Connect the AC load.
For safe installation:
• The neutral conductor (N) of the AC output of
the AC Master must be connected to the safety
ground (PE/GND).
• Integrate a ground fault circuit-interrupter
(GFCI/RCD) in the wiring of the AC output.
Refer to locally applicable regulations on these
issues!
Step 10. Check all wiring. When all wiring is OK: place the DC fuse(s) and close the fuse cover.
When the fuse is placed, internal capacitors may cause a spark. This is normal.
Step 11. Switch ON the AC Master.
ON
OFF
POWER SAVING

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AC Master
12/300, 12/500, 24/300, 24/500 – User and Installation Manual
8 Operation
Switching ON and Power Saving
Move the main switch to position I (ON) or II (POWER SAVING).
Power saving mode scans the output and compares the detected load to the threshold value (40W). If a
load is detected which is below the threshold value, the inverter switches to power saving mode. If a
load is detected higher than the threshold value, the inverter is switched on.
Switching OFF
Move the main switch to the position O (OFF). Note that switching off the AC Master does not
disconnect the batteries!
LED indicators
Output LED Sine Wave LED Power LED Meaning
Continuous (green) Continuous (green) Continuous (green) Inverter OK
Blinking (green) Blinking (green) Continuous (green) Power Saving
Off Continuous (red) Continuous (green) Inverter fault
Off Blinking slowly (red) Continuous (green) Battery voltage low/high
Off Blinking fast (red) Continuous (green) Short circuit
Off Off Off Inverter off

AC Master 12/300, 12/500, 24/300, 24/500 – User and Installation Manual
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9 Troubleshooting
Problem Possible cause What to do?
All LED indicators are off Main switch is set to the OFF
position.
Set the main switch in ON
position.
DC fuse(s) blown. Replace the fuse(s).
AC feedback, feedback
protection has caused the
inverter to switch off.
Remove AC power source for the
AC output and switch on the AC
Master. To avoid damage do not
install in parallel with another AC
source.
Output LED blinking green Power saving: Inverter is in
Power saving mode.
Increase the load or put the main
switch in position I.
Sine Wave LED continuously red
(Inverter fault)
Over temperature. Reduce the
load and let the inverter cool
down. It will switch on again
when the internal temperature is
sufficiently low.
Check the airflow through the
inverter. The operation of the
cooling fan may not be blocked.
Overload. Inverter attempts
restarting 5 times. If it still fails,
the AC Master remains in
Overload .
Reduce the load and/ or check
the AC wiring for possible short
circuits. Then reset the inverter
manually by switching the main
switch off and on again.
Fan fault. Contact your Mastervolt supplier.
Sine Wave LED blinking slowly
red (Battery voltage low/high)
DC input voltage too low (flat
battery).
Check the battery. At low
voltage, disconnect the load and
charge the battery. The inverter
will switch on again when the
input voltage is > 11.0V (22.0V).
DC input voltage too low: voltage
drops across the DC cables due
to too long or too narrow cables.
Reduce the length of the DC
cables or use cables with a
larger gauge.
DC input voltage is too high. Check battery voltage; switch off
charger. The inverter will switch
on again when the input voltage
is < 14.5V (29.0V).
Sine Wave LED blinking fast red
(Short circuit)
Inverter attempts a restart 5
times. If it still fails, the AC
Master remains in Short circuit.
Switch off the AC Master and
check the AC wiring. Only switch
the inverter on when the wiring
problem has been solved.

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AC Master
12/300, 12/500, 24/300, 24/500 – User and Installation Manual
10 Specifications
AC Master 12/300-230V AC Master 24/300-230V
Part number 28010302 28020302
General
Output voltage 230Vac (± 5%) –
50Hz (± 0.1%)
230Vac (± 5%) –
50Hz (± 0.1%)
Output waveform True sine True sine
Nom. battery voltage 12V 24V
Cont. power at 25°C, cos phi 1 300W 300W
Cont. power at 40°C, cos phi 1 250W 250W
Peak load 600W (5s, Uac>210V) 600W (5s, Uac>210V)
AC connection IEC 60320 - C13 (female) IEC 60320 - C13 (female)
Included IEC plug IEC 60320 - C14 (male) IEC 60320 - C14 (male)
Efficiency (Max) ≥ 90% ≥ 91%
Display/read-out 3 × LED 3 × LED
Dimensions, h×w×d 210 × 130 × 60mm 210 × 130 × 60mm
Weight 1.2kg 1.2kg
Approvals CE, E-mark CE, E-mark
Technical
Technology High frequency High frequency
DC input voltage range 10.0 – 15.5V 20.0 – 31.0V
Low battery voltage, switches off at 10.0V +/- 3 % 20.0V +/- 3 %
Low battery voltage, switches on at 11.0V +/- 3 % 22.0V +/- 3 %
High battery voltage, switches off at 15.5V +/- 3 % 31.0V +/- 3 %
High battery voltage, switches on at 14.5V +/- 3 % 29.0V +/- 3 %
Input current (nominal load) 27.8A 13.7A
No-load power consumption (ON mode) 0.67A @ 12V 0.33 A @ 24V
No-load power consumption (Power
Saving mode) 0.33A @ 12V 0.17 A @ 24V
DC fuse (integrated) 40A × 2 40A
DC Cable length (integrated) 1.5m 1.5m
Harmonic distortion typical < 6% < 6%
Cos phi All power factors allowed
Temperature range (ambient temp.) -20°C to 60, derating above 40°C
Cooling Fan
Protection degree IP23 (if vertically wall mounted)
Protections Over temperature, over load, short circuit, high/low battery
voltage