Relay Box - Fuse Box

Electrical central or PDM (Power Distribution Module), which is becoming more popular due to its flexibility. Read more about the topic further down this page.
- How does a relay box / fuse box work?
- Different variants
- Choosing a relay box
- Wiring
- Accessories
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How does a relay box / fuse box work?
An electrical central can have many names such as fuse box, fuse central, relay box, or relay central.
Instead of having separate fuses for each cable (inline fuse) and separate relays, these are neatly combined into an electrical central / relay box. This is then connected to the battery. Now you have X number of inputs and outputs for various components.
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Different Variants
Mechanical Electrical Central:
Where you mechanically customize your electrical central with mechanical fuses and relays. There are generally two variants of this type. The first is wired cables with a ready-made wiring harness that is connected. The alternative is a box without cables where you use ring terminals to connect or pin into connectors.

A digital module that has built-in solid state relays and fuses to distribute electronic signals safely in your application. This is a flexible variant that is becoming more popular.

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Choosing a Relay Box
When choosing an electrical central for your project, it is important to ensure that it has enough inputs and outputs as well as spaces for the relays and fuses you need. There are loose holders available for purchase, but it is better to have a complete system when investing in your project. Therefore, make sure to choose some extra inputs/outputs for your new electrical central. Also, ensure that the chosen electrical central has the functions you need regarding turn signal relays and other special relays.
Some examples of relays include:
- Starter Relay
- Fan Relay
- Fuel Pump Relay
- ECU Relay
- Turn Signal Relay

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Wiring
When installing an electrical central, it is very important to follow the wiring diagram to avoid short circuits. Make sure you have fuses and relays for the intended components.
Poor connections damage both the pins and the surrounding plastic due to heat buildup.
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Accessories
- Cabling
For a neat and safe connection of your electrical central. - Relays
To control your relay-dependent components. - Fuses
To protect against short circuits.
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Engine management / Electric
- Engine control system: The various parts available
- Ignition System Information
- Install motor control
- Pressure sensor - Information
- Temperature sensor - Information
- Buttons - Switches - Information
- Connectors - Information
- Cooling fan car - Information
- Exhaust gas temperature sensor - EGT Sensor
- Lambda sensor - Wide band lambda
- Relay - Information
- Relay box - Fuse central
- CAN protocol - Canbus
- Ethanol sensor - Information
- Gauges and Dash
- Trigger sensor information
- Dimensioning of cable [and fuse size]
- Distributor Problems (And Solution)
- How does an Ignition Coil work?