Battery & DC Wiring
Battery Type Selection
• Use only deep-cycle lead-acid batteries with this Inverter, such as 12 volt marine/RV deep-cycle batteries. Do not use automotive, engine starting (SLI), or maintenance-free wet cell batteries with this Inverter; they are designed for repeated, shallow discharge and will wear out quickly.
• Gel and AGM (Absorbed Glass Mat) batteries can be used with this Inverter, but they require special charging procedures. Refer to battery supplier’s instructions.
1. Unpack and inspect the Inverter, and make sure the power switch is in the OFF position.
Note: we recommend using Go Power! DC Install Kits when installing a Go Power! Inverter (sold separately).
2. Connect the DC Inverter cables into the power input terminals on the back of the Inverter. Remember, the (+) terminal is positive and the (-) terminal is negative. Place the lug connector between the washers and tighten the terminal screw or nut to clamp the wires securely. Ensure connections are tight.
3. Connect the ground cable to the appropriate location; see section on Grounding further in this article.
CAUTION! Equipment Damage. Loose connections result in excessive voltage drop and may cause overheated wires and melted insulation. Ensure connections are tight.
4. First, connect the DC Inverter cables from the negative terminal of the Inverter to the negative terminal of the battery. Make sure the connection is secure.
5. Before proceeding further, carefully check that the cable you just connected is going from the negative terminal of the Inverter to the negative output terminal of the battery.
6. Install the Inverter fuse into the positive lead. The fuse should be located within 12” (31 cm) of the battery. Ensure all connections are tight and secure.
7. Connect the cable of the positive terminal of the Inverter to the positive terminal of the battery. Make a secure connection. Check your polarity.
WARNING! Fire/explosion Hazard.
You may observe a spark when you make the final battery connection since current may flow to charge capacitors in the Inverter. Do not make this connection in the presence of flammable fumes, as explosion or fire may result.
CAUTION! Equipment Damage.
This Inverter cannot supply power to any AC distribution wiring or AC loads in which the neutral and ground are connected (bonded). Doing so will destroy the unit and void the warranty. If you do not understand neutral to ground bonding, please have a professional install your system for you. See section on Grounding further in this article.
8. Set the power switch to the ON position. Check the meters and indicators on the front panel of the Inverter. The Function LEDs should be green showing the Inverter is ON. If it does not, check your battery bank and the connections to the Inverter. The other indicators should be OFF.
9. Set the Inverter switch to the OFF position. The indicator lights may blink and the internal alarm may sound momentarily. This is normal. Plug the test load into the AC receptacle on the front panel of the Inverter.
10. Set the Inverter switch to the ON position and turn the test load on; the Inverter should supply power to the load. If you plan to measure the output voltage of the inverter, a true RMS meter must be used for accurate readings.
Battery Precautions
1. Wear splash-resistant ANSI-approved safety goggles and electrically-insulated gloves while working near batteries.
2. Charge, store, and maintain batteries according to supplier’s instructions.
3. Locate batteries in a clean, well-ventilated area, away from ignition sources and flammable materials. Vented lead-acid batteries release explosive hydrogen gas while charging.
4. Only connect similar batteries together. Do not connect old and new batteries together, flooded and gel cells together, or batteries of different capacities together.
5. Only connect this Inverter to a 12V nominal battery bank. Do not attempt to connect the Inverter to any other power source other than a battery with a nominal output voltage of 12 volts or damage to the Inverter may occur and will void the warranty.
6. Connect batteries in parallel ONLY (negative terminals together to one cable; positive terminals together to the other cable).
7. Install a properly rated fuse on the positive output of the battery bank. See section on DC Wiring further in this article.
The following points must be observed for the DC Wiring:
• The DC positive and negative cables connected to the Inverter from the battery bank should be linked together with zip ties or electrical tape every 6”. This helps to reduce radio frequency interference and reduces the effects of inductance both of which improve the Inverter waveform and reduces the wear of the Inverters filter capacitors.
• To ensure optimum Inverter performance the number of connections between the battery bank and the Inverter unit should be minimized except from the over-current and battery disconnect devices. All additional connection points will cause extra voltage drops.
• The Battery bank voltage must match the DC voltage required by the Inverter, which is 12V.
• All DC cable wire terminations should use a crimped and sealed copper ring terminal lugs.
• Make sure all cables have a smooth bend radius and no kinks are present.
• Colour code all DC Cables coming to/from the battery bank.
Use coloured electrical tape or heat shrink tubing. Red for positive (+), Black for negative (-) and Green for DC ground.
DC Wiring Sizing
The distance between the battery bank and the Inverter should be as short as possible to achieve maximum efficiency and to reduce fire hazards. The gauge of the cable should be sized appropriately to limit the voltage drop to less than 2% when carrying the maximum input current to prevent frequent low-input voltage warnings and shutdown. Only use high quality copper wire.
The cables should be as short as possible and the overall length of both cables added together should be less than 10 ft (3 m) to comply with code requirements. Keeping your wire runs as short as possible helps to prevent: low voltage shutdowns and nuisance tripping of the DC breaker because of increased current draw. The table below shows the recommended DC cable size, fuses/circuit breakers and DC grounding cable sizes for the Inverter (note: these values are correct for cables in free air, not conduit).
Model | Wire AWG | Inline Fuse / Circuit Breaker |
GP-1750HD | #2 | F-200 |
GP-3000HD | 4/0 | F-400 |
GP-5000HD | 4/0 | F-400 |
We recommend using a Go Power! Inverter Fuse and Cable Install Kit when installing your Go Power! Inverter (sold separately). Our Install Kits include 10’ of large gauge battery cables and tie downs, as well as the appropriate inverter fuse and fuse block—everything you need to properly connect your Inverter to your batteries. The table below shows which Install Kit will work with your Inverter.
Model | Go Power! Inverter Fuse and Cable Install Kit (GP-DC-KITS) |
GP-1750HD | GP-DC-KIT3 |
GP-3000HD | GP-DC-KIT5 |
GP-5000HD | GP-DC-KIT5 |
DC Grounding
To protect against electrical shock hazards, the Inverter metal chassis must be connected to the DC grounding system. The DC grounding system is sometimes referred to as the Earth ground or another designated ground. For example on an RV, the metal frame of the RV is designated as the negative DC ground / RV ground.
The DC ground wire connection on the Inverter is used to connect the exposed chassis of the Inverter to the DC grounding system. Use copper wire that is either bare or provided with green insulation. The size of this conductor should be coordinated with the size of the over-current devices used.
DC grounding involves proper grounding of the negative of the battery, the DC panel and the DC side of the Inverter. The DC panel is normally used to connect the batteries and distribute DC power to the Inverter and to the other DC loads.
A common earth ground should be used to bond the Inverter, negative bus bar and the negative battery terminal. All connections must be tight against bare metal. Use star washers to penetrate paint and corrosion.