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Details the capabilities of the Solid State Relay Block, including voltage, branch protection, and status indicators.
Explains the main power supply connection and how the protection circuits function and reset.
Guides on connecting the main power, ground, and activation wires for the relay module.
Describes how to activate the relay channels by applying 12V to the appropriate upper level terminals.
Explains how to activate the relay channels by applying ground to the appropriate lower level terminals.
Details the function of diagnostic LEDs for troubleshooting wiring, short circuits, or excessive current.
Illustrates common wiring setups for the Solid State Relay Module, including fan and fuel pump connections.
Shows a wiring diagram for combining channels for devices requiring higher current ratings.
Outlines the process for warranty repairs, including proof of purchase and Return Material Authorization (RMA).
The MSD Solid State Relay Block, available as PN 7564 (Red) or PN 75643 (Black), is a robust electronic module designed to manage and distribute power to various automotive components. It acts as a sophisticated power distribution unit, offering a modern alternative to traditional mechanical relays by utilizing solid-state technology for enhanced reliability and control.
The primary function of the Solid State Relay Block is to provide a controlled and protected power supply to up to four independent electrical branches within a vehicle. It receives a main power input, typically from the positive battery post, and then distributes this power to individual outputs based on activation signals. Each of these four branches is capable of handling a significant current load, making the device suitable for powering a wide range of accessories such as fuel pumps, cooling fans, lighting, or other high-current devices.
A key aspect of its operation is the integrated protection circuitry. Each independent branch is equipped with thermal protection against overload and electrical shorts. This means that if a connected device draws excessive current or experiences a short circuit, the relay block will automatically trip the protection for that specific channel, preventing damage to the device itself, the wiring, and other vehicle components. This automatic protection significantly enhances the safety and longevity of the electrical system.
The device is designed for versatile activation, allowing each output branch to be controlled by either a 12-volt signal or a ground signal. This flexibility ensures compatibility with various vehicle wiring schemes and control systems. Once a protection circuit has tripped due to a fault, the activation signal for the affected channel(s) must be removed and then re-applied to reset the channel and restore power. This manual reset mechanism ensures that the user is aware of a fault and can address the underlying issue before power is restored.
The Solid State Relay Block also incorporates diagnostic LED indicators for each relay branch. These LEDs provide visual feedback on the status of each channel, assisting in troubleshooting wiring problems, identifying short circuits, or detecting excessive current draws. This diagnostic capability simplifies the process of identifying and resolving electrical issues within the vehicle's system.
The Solid State Relay Block is engineered for ease of integration and reliable performance in automotive environments. Its compact design and versatile mounting options allow for flexible placement within the vehicle. However, it is crucial to mount the module in a sturdy, dry location, away from extreme heat, and it should not be immersed in liquids or subjected to direct spray from a power washer to ensure its longevity and proper function.
For optimal performance and safety, proper wiring is paramount. The main power feed and distribution wires, which connect to the large terminals, must be sized according to the provided wire size selection guide to adequately handle the combined current load. All other control and ground wires can typically be of a smaller gauge. It is critical to securely connect the main power terminal to the positive battery post, ensuring that the power wire is attached to the relay block before connecting it to the battery, and disconnected from the battery before removing it from the relay block. A dedicated ground connection for the module is also essential for both 12V and ground activation configurations.
The activation of each output branch is straightforward. For 12V activation, a 12-volt signal is applied to the corresponding upper-level terminal. For ground activation, a ground signal is applied to the corresponding lower-level terminal. This dual activation capability allows for integration with various switches, control modules, or existing vehicle wiring.
The device also supports combining two or more channels for applications requiring more than a 20-amp single-channel rating. This feature allows for greater current capacity for high-demand devices, providing flexibility in system design.
The Solid State Relay Block is designed for minimal maintenance, primarily focusing on proper installation and diagnostic assistance. The diagnostic LED indicators are a key maintenance feature, providing immediate visual cues for troubleshooting. If a fault occurs, the LEDs will indicate whether the issue is an output fault (due to 12V applied directly to the output or a faulty unit) or a power/ground fault (due to over-current, missing battery power, or missing ground). This allows users to quickly pinpoint the general nature of the problem without extensive electrical testing.
To reset a faulted channel, the activation signal for that channel must be deactivated and then re-activated. This simple reset procedure helps confirm that the underlying issue has been addressed before power is restored.
The included Loctite® Threadlocker 242® packet for securing threaded screws is a thoughtful detail that contributes to the long-term reliability of the installation by preventing screws from loosening due to vibration. Applying a small amount of this medium-strength threadlocker ensures that connections remain secure over time, reducing the need for re-tightening.
In the event of a malfunction that requires repair, MSD provides a warranty service. For warranty claims, proof of purchase is required. If the warranty period has expired, repair services are available for a fee. When returning a unit for repair, it is important to obtain a Return Material Authorization (RMA) number beforehand. Additionally, leaving all wires at their installed length and providing a detailed account of any problems experienced, along with a list of installed components and accessories, will assist in the repair process, ensuring efficient service and accurate diagnosis. This comprehensive approach to service and repair underscores the commitment to supporting the product throughout its lifespan.
General| Type | Electromechanical Relay |
|---|---|
| Load Current | 10A |
| Ambient Temperature | -40°C to +85°C |
| Load Voltage | 250V AC/30V DC |
| Contact Form | 1 Form C |
| Contact Rating | 10A 250V AC/30V DC |
| Operate Time | 10 ms (max) |
| Release Time | 5 ms (max) |
| Insulation Resistance | 1000MΩ min |
| Dielectric Strength | 1500V AC for 1 min |
| Control Voltage | 5V DC |
| Coil Voltage | 5V DC |
