At a Glance
- SKU: B40A
PRODUCT INFORMATION
Product Details
12 Volt DC Power Trailer Circuit Breaker - 40 Amp Rating - Auto Reset (B40A)
Part # B40A
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Trailer Electrical / DC Circuit Protection
12 Volt DC Power Trailer Circuit Breaker - 40 Amp Rating - Auto Reset
A 40 amp, 12 volt DC auto-reset circuit breaker for protecting trailer, automotive, utility, and other compatible low-voltage DC wiring systems from overload conditions.
Part Number: B40A 40 Amp Rating 12 Volt DC Auto Reset
Key Measurements & Specs
| Specification | Detail |
|---|---|
| Part Number / SKU | B40A |
| Brand | R&P Carriages |
| Product Type | DC power circuit breaker |
| Voltage Rating | 12 Volt DC |
| Amp Rating | 40 Amp |
| Reset Type | Auto reset |
| Material / Finish | Not specified |
| Quantity Included | 1 circuit breaker |
Fitment / Application
| Category | Details |
|---|---|
| Vehicle / Trailer / System | Compatible 12V DC electrical systems |
| Primary Fit | Trailer, automotive, utility, and low-voltage DC circuit protection where a 40 amp breaker is required |
| Fitment Method | Match voltage, amp rating, wiring requirements, terminal style, and mounting style before installation |
| Important Note | Verify before ordering. Circuit protection should match the wire gauge, circuit load, and application requirements. |
Top Features
| Feature | Buyer Benefit |
|---|---|
| 40 Amp Rating | Supports compatible DC circuits requiring 40 amp overload protection. |
| 12 Volt DC Use | Designed for compatible low-voltage DC electrical systems. |
| Auto Reset | Resets automatically after a trip condition clears and the breaker cools. |
| Overload Protection | Helps protect wiring and connected components from excessive current draw. |
Overview
The B40A is a 12 volt DC power circuit breaker with a 40 amp rating and automatic reset function. It is used to help protect compatible wiring systems from overload conditions by interrupting current flow when the circuit is overloaded. Once the overload condition clears and the breaker cools, the circuit breaker can reset automatically.
R&P Service Insight
A circuit breaker should be selected based on the electrical system, wire gauge, expected current draw, and required circuit protection. Do not oversize a breaker to compensate for wiring or component problems.
- Match the circuit: Confirm the circuit requires a 40 amp breaker before installation.
- Protect the wiring: The breaker rating should be appropriate for the wire gauge and load.
- Check the fault: If the breaker repeatedly trips, inspect the circuit for overload, short, damaged wiring, or incorrect component draw.
R&P Knowledge Hub
Compatibility: Compatible with 12V DC systems where a 40 amp auto-reset breaker is the correct circuit protection choice. Verify before ordering.
Vehicle / System Fit: Commonly used for trailer, automotive, utility, and general low-voltage DC wiring applications when the circuit specifications match.
Installation Notes: Confirm terminal style, mounting style, wire gauge, circuit load, and electrical routing before installation.
Performance Insight: Auto-reset breakers are intended to interrupt current during overload conditions and restore continuity after the breaker cools and the fault condition clears.
Brand & Fitment Note
Selling Brand: R&P Carriages
Application Reference: Trailer, automotive, utility, and other 12V DC references describe application fitment only when the electrical specifications match.
What This Means: This listing is for an R&P Carriages 12V DC 40 amp auto-reset circuit breaker. It is not being sold as a guaranteed OEM-branded item unless specifically stated and verified.
Before Ordering: Verify voltage, amp rating, terminal style, mounting style, wiring size, circuit load, and included components before installation.
R&P Repair Insight
Repeated breaker cycling is usually a sign that the electrical circuit needs inspection. The breaker is a protection device, not a repair for an overloaded or damaged circuit.
- Check circuit load: Make sure the connected accessories do not exceed the circuit's intended capacity.
- Inspect wiring: Look for damaged insulation, loose connections, corrosion, pinched wires, or short-to-ground conditions.
- Verify rating: Replace with the correct amp rating for the application. Do not install a higher-rated breaker unless the wiring and system are designed for it.
Features
40 Amp Circuit Protection
Rated for compatible 40 amp DC circuits where overload protection is required.
12 Volt DC Application
Intended for compatible 12V DC electrical systems used in trailer, automotive, and utility wiring applications.
Automatic Reset Function
Auto-reset design restores circuit continuity after the breaker cools and the overload condition clears.
Wiring System Protection
Helps protect the electrical system by interrupting current flow when excessive load is present.
Included Components
| Quantity | Item |
|---|---|
| 1 | 12 Volt DC Power Circuit Breaker - 40 Amp Auto Reset |
| Not specified | Mounting hardware, nuts, terminals, and wiring are not specified as included. Verify package contents before installation. |
Important Fitment Note: Verify voltage, amp rating, wire gauge, terminal style, mounting style, circuit load, and included components before installation. Circuit protection must be matched to the wiring and application. If the breaker repeatedly trips, inspect and correct the electrical fault before continued use.
R&P Carriages B40A 12 volt DC power circuit breaker, 40 amp auto reset circuit breaker, 12V DC breaker, trailer wiring circuit breaker, automotive DC circuit protection, overload protection breaker, auto reset breaker for 12 volt wiring systems, trailer electrical parts, utility trailer wiring protection.
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