9E
• Connect DC Wiring:
Though your
Inverter/Charger is a high-efficiency con-
verter of electricity,
its rated output
capacity is limited
by the length and
gauge of the
cabling running
from the battery to
the unit. Use the
shortest length and
largest diameter
cabling (maximum
2/0 gauge) to fit
your Inverter/
Charger's DC input
terminals. Shorter
and heavier-gauge
cabling reduces DC voltage drop and allows
for maximum transfer of current. Your
Inverter/ Charger is capable of delivering
peak wattage at up to 200% of its rated con-
tinuous wattage output for brief periods of
time. See your unit's Specifications Sheet
for details. Heavier-gauge cabling should be
used when continuously operating heavy
draw equipment under these conditions. For
EMS1250UL and EMS2012UL, tighten
your Inverter/ Charger and battery terminals
to approximately 3.5 Newton-meters of
torque to create an efficient connection and
to prevent excessive heating at this connec-
tion. Model EMS1012 comes with two
Quick Connectors, one prewired to the unit
and one in the box, for use with user-sup-
plied cables. Insufficient tightening of the
terminals could void your warranty. See the
Minimum Recommended Cable Sizing
Chart on your unit's Specifications Sheet.
• Connect Ground:
Using a #8 AWG wire
or larger directly connect the Main Ground
Lug to the vehicle's chassis or earth ground.
See the Feature Identification section, page
3, to locate the Main Ground Lug on your
specific Inverter/Charger model. All instal-
lations must comply with national and local
codes and ordinances.
• Connect Fuse:
NEC article 551 requires
that you connect your Inverter/Charger's
positive DC Terminal directly to a UL-listed
fuse and fuse block within 18 inches of the
battery. The fuse's rating must equal or
exceed the Minimum DC Fuse Rating listed
for your Inverter/Charger. See your unit's
Specifications Sheet for fuse requirements.
See diagrams below for proper fuse
placement.
Battery Connection
Vehicular
Your Inverter/Charger’s Nominal DC Input Voltage
must match
the voltage of your battery or batteries—12 Volts in most vehicular applications.
Although it is possible to connect your Inverter/Charger to the main battery within your vehicle’s electrical system, in the normal vehicular context,
the Inverter/Charger will be connected to one or more dedicated auxiliary (house) batteries which are isolated from the drive system to prevent possible
draining of the main battery.
12 Volt Inverter/Charger
12 Volts
12 Volts
3
5
12 Volt Main Battery Connection
12 Volt Alternator
Vehicle Battery Ground
12 Volt Main Battery
12 Volt Auxiliary (House) Battery
UL-Listed Fuse & Fuse Block (mounted
within 18 inches of the battery)
Battery Isolator
Large Diameter Cabling, Maximum(2/0) Gauge to Fit Terminals
7
6
5
4
3
2
1
12 Volt Inverter/Charger
12 Volts
12 Volts
12 Volts
12 Volt Main and Auxiliary (House) Battery Connection (Isolated Parallel)
1
4
1
7
6
2
5
7
3
2
Connect your Inverter/Charger to your batteries using the following procedures:
WARNING! • Failure to properly ground your Inverter/Charger to the vehicle’s chassis or earth
ground may result in a lethal electrical shock hazard.
• Never attempt to operate your Inverter/Charger by connecting it directly to output from an
alternator rather than a battery or battery bank.
Front-Mounted DC
Connectors
(EMS2012UL only)
EMS1012UL Inverter/Chargers feature two
Quick Connectors (one wired to the unit and
one included in the box) for use with user-supplied
cables. EMS1250UL and EMS2012UL use
direct DC battery connection, illustrated at the
top of the page.
EMS1012UL Inverter/Chargers feature two
Quick Connectors (one wired to the unit and one
included in the box) for use with user-supplied
cables. EMS1250UL and EMS2012UL use direct
DC battery connection, illustrated at the top of
the page.
2
Rear-Mounted DC Conn-
ectors (EMS1250UL only)