Do 7-Way Trailer Connectors have Amp Ratings for Pins or the Whole Socket
Question:
I have a RV hookup cable for the tow vehicle that has different gauges of wire for the seven wires. The black power / charge wire and white ground wire are both 10 gauge. Does this part have a specification rating for continuous or intermittent use in amps per pin or the entire assembly? I would like to the correct circuit breakers to protect the pins and socket from overheating. The connection would charge the RV battery while the engine is running.
asked by: Wade
Expert Reply:
Most if not all trailer wiring harnesses/connectors use larger wires for the 12 volt and ground circuits compared to the other circuits (lights). The sockets themselves don't have an amperage rating so you will go by the draw of the things drawing power.
In order to figure out what the lights are drawing you could connect the trailer to the tow vehicle and turn on a function while testing the trailer side wiring behind the connector with a meter to see what sort of reading you get. Usually running lights (including tail lights, clearance lights, and marker lights) draw around 7 to 10 amps unless they are LED lights. Brake lights and turn signals are usually 2 to 3 amps and are combined on the same circuit.
For a 12 volt circuit we recommend a 40 amp circuit breaker # PK54540. For a brake controller I recommend a 30 amp, # PK54530. And if the trailer has reverse lights it will be less than brake and turn signals so maybe 5 amps total.
Unless there is a short though the wiring, pins, and sockets are not likely to ever overheat during normal operation. Also, the 12 volt circuit on a 7-Way can only provide a maintenance charge to a trailer battery. The only time it can charge it up is if it is a breakaway battery which would have a 5 amp hour rating. The wiring is not large enough and the alternators on most vehicles is not strong enough to push back the required amperage to charge up a regular sized 12 volt battery. To do that you would need a Dual Battery charger like # 331-BCDC1240D.
Products Referenced in This Question
Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp
- Battery Charger
- Battery Charger
- RV/Camper
- Trailer
- 200 Ah
- Charges/Maintains
- 12V
- Solar Panels to Auxiliary Battery
- Vehicle Battery to Auxiliary Battery
- Redarc
more information >
Pollak Circuit Breaker - Cycling/Automatic Reset - 30 Amp - Straight Mount Bracket
- Accessories and Parts
- Wiring
- Circuit Breaker
- 30 Amp
- Pollak
more information >
Pollak Circuit Breaker - Cycling/Automatic Reset - 40 Amp - Straight Mount Bracket
- Accessories and Parts
- Wiring
- Circuit Breaker
- 40 Amp
- Pollak
more information >
Product Page this Question was Asked From
Hopkins Endurance Multi-Tow 7-, 5- and 4-Way Flat Trailer Connector - Vehicle End - Ergonomic Design
- Trailer Wiring
- Trailer Connectors
- Vehicle End Connector
- Plug Only
- 4 Flat
- 5 Flat
- 7 Blade
- Hopkins
more information >
Featured Help Information
Instructions
Miscellaneous Media
Continue Researching
- Shop: Trailer Wiring
- Shop: Brake Controller
- Shop: Suspension Enhancement
- Shop: Trailer Hitch
- Article: Parts Needed to Add Hydraulic Disc Brakes to a Trailer
- Shop: Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Shop: Redarc Tow-Pro Liberty Brake Controller - Dash Knob - 1 to 2 Axles - Proportional
- Article: Trailer Wiring Diagrams
- Shop: Mounting Panel for Redarc Tow-Pro Trailer Brake Controller Control Knob
- Shop: Hydrastar Electric-Hydraulic Actuator w/ Line Kit for Disc Brakes - 1,600 psi
- Shop: Seaflo Battery Disconnect Switch for Boats and RVs - On/Off - 900 Amps
- Shop: Hydrastar Electric Over Hydraulic Actuator Kit for Disc Brakes - 1,600 psi
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Shop: Curt Echo Wireless Brake Controller - 7-Way Plug Mount w/ Bluetooth App - 1 to 2 Axle - Proportional
- Shop: Vehicle Tow Bar Wiring
- Shop: Base Plate for Tow Bar
- Shop: Roof Rack
- Video: Best Trailer Brake Options
- Q&A: What is the Maximum Amperage Draw Rating for a 7-Way Trailer Connector
- Q&A: The Function of the Auxiliary 12-Volt Connection on the 7-Way Trailer Connection
- Search Results: tmk52vr
- Q&A: Can I Charge My Trailer Battery Using 7-Way Trailer Connector on Truck
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Q&A: 7-Way Trailer Connectors Compatible with 8 Gauge Wires for 12V Power and Ground
- Video: Peterson Great White LED Mini Utility Light Review and Installation
- Q&A: How To Install the HappiJac Qwik-Load Upgrade Kit for Standard Turnbuckles
- Q&A: Will RoadActive Suspension Kit Fit with Air Lift Air Bags on a 2012 Ford F-250
- Search Results: walking beam
- Search Results: disc brake line kit
- Article: Brake Controller Installation: Starting from Scratch
on Trailer Wiring
Robert S.
7/20/2020
I bought the curt echo brake controller, which lights off another vehicle but notthe one I am installing on. Ihave the 12 to the brake pins but not the battery pin (I only have 20 amps) is that why the led will not light? Does it require aux power and brake power? thanks