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Stinger SGP35 500 Amp High Current Relay
$160.99
In stock
SKU
SGP35
Expert Knowledge
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- 500 Amp Solenoid relay
- Prevents primary battery discharge
- Ideal for 2nd audio battery isolation from vehicle systems
- 500A constant 900A peak current
The 500 Amp Relay and Isolator protects your primary battery from unnecessary discharge while delivering maximum current output. Designed for isolating a secondary audio battery from your vehicle’s electrical system, it uses high-current relays that provide a reliable and efficient solution for adding extra batteries. Encased in water-resistant black plastic, this unit is rated for 100,000 mechanical cycles and supports 500A continuous and 900A peak current.
Unit includes: High current relayStinger SGP35 500 Amp High Current Relay
- Handles 500-amp continuous current and 900-amp surges
- Durable weatherproof construction
- A must for multi-battery systems, allows for longer battery life and control over which battery is being used.
- Great for isolating a second battery making it dedicated to the stereo system
- Does not create a voltage drop to the second battery like conventional isolators
- 100,000 mechanical cycle life
- Compatible with all types of alternators and charging systems
| Manufacturer | Stinger |
|---|---|
| Part Number | SGP35 |
| Operation Voltage | 8-15 Volt DC |
| Relay type | High Current |
| Pole switching type | SPST (Single pole Single throw) |
| Tab type | Metal Tab |
| Waterproof ingress protection | IP69K - Dust; High Pressure and Temperature rating |
| Warranty | 1 Year |
| California Proposition 65 |  Warning: This product can expose you to chemicals including di(2-ethylhexyl)phthalate (DEHP), which is [are] known to the State of California to cause cancer or birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov |
| UPC Code | 609098800365 |
| Return period | 30 days |
| Exchange period | 30 days |
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Relay Pinout Diagrams Explained
A relay pinout diagram shows the function of each terminal (pin) on a relay and how the internal connections work. It helps you wire the relay correctly for your project.
1. Basic Relay Anatomy
Most automotive relays have two main parts:
- Coil – An electromagnet that switches the relay on/off (low current side)
- Switch Contacts – The high-current switch that turns your accessory on/off
2. Most Common Automotive Relay: 5-Pin SPDT
This is the standard relay type used with sockets like BRSCN, BRSPC, BRSS, etc.
| Pin | Name | Function |
|---|---|---|
| 30 | Common | Power input (goes to the load) |
| 87 | Normally Open (NO) | Closed when relay is energized (ON) |
| 87a | Normally Closed (NC) | Closed when relay is de-energized (OFF) |
| 85 | Coil Ground | Negative side of coil |
| 86 | Coil Positive | Positive side of coil (+12V trigger) |
Visual Pinout Diagram
87
│
87a ───┼─── 30
│
[Relay]
85 ───────── 86
How It Works:
- No power to 85/86 → Current flows between 30 and 87a
- +12V applied to 85/86 → Coil energizes → Current flows between 30 and 87
4. How to Read a Relay Pinout Diagram
Most relay pinout diagrams include the following elements:
- A box or outline representing the relay body
- Pin numbers clearly labeled next to each terminal
- Internal connections shown with lines or dotted lines
- Coil symbol (usually a rectangle or spring-like coil)
- Switch contacts shown with an arrow indicating movement when the relay is energized
Example Relay Pinout Diagram:
87 30
│ │
└──────┬────┘
│
┌──┐ ← Moving Contact
└──┘
/ \
87a (Switches when coil is energized)
85 ───────────── 86
Coil
Understanding the Symbols:
- 30 — Common terminal (input power)
- 87 — Normally Open (NO) contact
- 87a — Normally Closed (NC) contact
- 85 & 86 — Coil terminals (control side)
When the relay coil is energized (pins 85/86 powered), the internal switch moves from 87a to 87.
Quick Wiring Examples (5-Pin Relay)
1. Basic On/Off Circuit (Most Common)
Used for lights, fans, fuel pumps, horns, etc.
- 86 → Switched +12V (from switch, toggle, or ECU output)
- 85 → Ground (or switched ground)
- 30 → Constant +12V Power (from battery or fuse box)
- 87 → Output to Accessory (lights, fan, etc.)
- 87a → Not used (leave disconnected)
2. Changeover / Dual Circuit Setup
Use both 87 and 87a when you need to switch between two different circuits.
- 30 → Input Power
- 87 → Circuit A (ON when relay is energized)
- 87a → Circuit B (ON when relay is OFF)
- 85 & 86 → Coil control
3. Typical Pin Connections Summary
| Pin | Connection | Typical Wire Color | Purpose |
|---|---|---|---|
| 30 | Constant +12V | Black (BRS14E & BRS12E) | Power Input |
| 87 | To Accessory | Green (BRS14E & BRS12E) | Power Output (ON) |
| 87a | Optional 2nd Circuit | Blue (BRS14E & BRS12E) | Power Output (OFF) |
| 85 | Ground | White (BRS14E & BRS12E) | Coil Negative |
| 86 | Switched +12V | Red (BRS14E & BRS12E) | Coil Positive |
Tip: Always use a fused power source on pin 30 for safety.
Basic 5-Pin Relay Wiring Harness
Battery +12V ──► [Fuse] ──► Pin 30 (Common)
Pin 87 ──► Accessory (Lights / Fan / Pump / Amp etc.)
Pin 86 ──► Switched +12V Trigger
(from switch, headlight wire, remote turn-on, etc.)
Pin 85 ──► Ground
Pin 87a ──► (Optional - Not used in basic setup)
Recommended Wiring (Empty relay socket or spade connectors (Not BRS14E & BRS12E):
- Pin 30 — Red wire with inline fuse (closest to battery)
- Pin 87 — Red or Blue wire to device
- Pin 86 — White or Pink trigger wire
- Pin 85 — Black ground wire
Dual Output (Changeover) Relay Harness
Pin 30 → Constant +12V (Fused)
Pin 87 → Circuit A (ON when relay activated)
Pin 87a → Circuit B (ON when relay is off)
Pin 86 → Trigger +12V
Pin 85 → Ground
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