I bought a new ridgeline earlier this year and went from a 2019 RTL-E to a 25 RTL. With the trim downgrade the truck was missing a lot of things including an AC inverter. I however wasn’t that impressed with the Honda’s inverter and its limitations and was happy to do an install myself that would be more capable.
I did some initial testing to determine the loading capabilities of the alternator and they seem to match fairly closely to the 400w unit Honda provides. I set my truck up for 700w continuous, 1400w surge (0.5s). However testing shows at idle you would want to do much more than 500w at the outlet, while driving you could get more.
With roughly 60 amps continuous, I settled on 4 gauge wire.
Alternator loading test:
I now need to route my wire from the battery to a junction under the driver seat. I planned to break off a high current connection to the center console and then continue back towards the rear seats where the inverter would live. I also planned to continue the run to the bed of the truck also. Also I would need to run from the inverter to the center console and to the bed ac lines.
Thanks to Gibson99 on his suggestion to route the wire through the driver side wheel well and chase a TPMS wiring through the firewall. It barely fit but did work!
This is driver side inner wheel well with the cover removed following the hood release cable.
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With the wire routed I pulled the rear seats completely and started building brackets to hold the inverter. I used bent aluminum to make the custom brackets and take advantage of some existing holes. They turned out okay and serve their purpose. I did however make a mistake and had to move the inverter toward the center of the cab by about 4 inches. I lucked out and was still able to use 2 of the three brackets and is still extremely strong.
Final position:
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First gen bracket, had to remove far right one:
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This was before I realized inverter was too far to the right:
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Console with outlet and dc connections:
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Cutting console on the cnc mill, very stressful since it is so visible:
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exiting the cab on passenger side with dc bus and ac:
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Bed with high current dc connections and ac outlet. Somehow managed to mess up the positioning of the surlok connectors. I had originally planned to do an aluminum plate that would attach making it way easier to cut off thr
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Rear fender well connections (I’m pretty sure I added some more zip ties after this) too, white wire is ac ground:
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All in all it has worked great and I’ve already used it a ton. Charging ebike, rc cars and quadcopters, charging battery power stations, etc.
I did some initial testing to determine the loading capabilities of the alternator and they seem to match fairly closely to the 400w unit Honda provides. I set my truck up for 700w continuous, 1400w surge (0.5s). However testing shows at idle you would want to do much more than 500w at the outlet, while driving you could get more.
With roughly 60 amps continuous, I settled on 4 gauge wire.
Alternator loading test:
- Idle no load 14.4v
- >40 amps makes voltage at the battery drop below 14v @ ~700rpm idle
- 60a 14.06v at 1050rpm
I now need to route my wire from the battery to a junction under the driver seat. I planned to break off a high current connection to the center console and then continue back towards the rear seats where the inverter would live. I also planned to continue the run to the bed of the truck also. Also I would need to run from the inverter to the center console and to the bed ac lines.
Thanks to Gibson99 on his suggestion to route the wire through the driver side wheel well and chase a TPMS wiring through the firewall. It barely fit but did work!
This is driver side inner wheel well with the cover removed following the hood release cable.
With the wire routed I pulled the rear seats completely and started building brackets to hold the inverter. I used bent aluminum to make the custom brackets and take advantage of some existing holes. They turned out okay and serve their purpose. I did however make a mistake and had to move the inverter toward the center of the cab by about 4 inches. I lucked out and was still able to use 2 of the three brackets and is still extremely strong.
Final position:
First gen bracket, had to remove far right one:
This was before I realized inverter was too far to the right:
Console with outlet and dc connections:
Cutting console on the cnc mill, very stressful since it is so visible:
exiting the cab on passenger side with dc bus and ac:
Bed with high current dc connections and ac outlet. Somehow managed to mess up the positioning of the surlok connectors. I had originally planned to do an aluminum plate that would attach making it way easier to cut off thr
Rear fender well connections (I’m pretty sure I added some more zip ties after this) too, white wire is ac ground:
All in all it has worked great and I’ve already used it a ton. Charging ebike, rc cars and quadcopters, charging battery power stations, etc.
