Haltech PD16 Power Distribution Module

Posted By: Steve Baur

Jun 13, 2022

WHAT IS POWER DISTRIBUTION

Power Distribution (in the automotive wiring world) is the method of physically distributing 12V power throughout the vehicle. In years gone past, this task was typically performed through a series of mechanical switches, relays, and fuses. Not unlike the 6-channel relay box that comes with Haltech Premium wiring harnesses.

A Power Distribution module (like the new Haltech PD16), is just like this mechanical fuse relay box, but smarter. Just like a fuse block, it has a main power input and outputs that turn devices like fans and pumps on or off. But unlike your conventional fuse relay block, there are no mechanical contacts and no physical fuses to blow.

With the PD16, all of the on and off switching is done with solid-state drivers and fuse currents are set digitally by the end-user. So in essence, the PD-16 replaces your mechanical relays and fuses.

HOW DOES A POWER DISTRIBUTION MODULE MAKE WIRING EASIER AND SAFER?

With a Power Distribution module your wiring is more intuitive, easier to troubleshoot, and safer. Because we’ve eliminated all fusible links or relays there is no chance of electro-mechanical failures. Additionally, solid-state drivers are fully programmable, so you can change your triggers/switches on the fly without any physical re-wiring.

Let’s say we want to turn on our electric fan at 170 degrees, but also when the A/C compressor is turned on, or even turn off the fan if the vehicle is moving at highway speeds? This can all be done using logic within the NSP software.

The PD16 also allows a user to monitor current draw in real-time, set programmable fuse limits and, because those fuse limits are set digitally, they can also be reset digitally which means if a circuit does go over current for any reason you can program the PD16 to reset the fuse after a certain time period.

The more familiar you become with your PD16, the more you will be able to take advantage of its customizable options. That’s the beauty of this system, it truly is infinitely customizable. You can make it as simple or as complicated as you want it to be while running the minimum amount of wiring necessary.

HOW IS HALTECH’S PD16 DIFFERENT TO OTHER PDMS?

The PD16 has been designed to integrate directly with Haltech’s Elite and Nexus series devices. What that means is your Haltech ECU and your Haltech PD16 are programmed using the same NSP software. WIth other PDM systems, setting up and programming outputs and channel functions can be quite a labor-intensive task, but with the Haltech PD16 once the power wiring is complete you simply plug the PD16 into the ECU CAN bus and it’s automatically recognised on the bus.

HOW DOES IT ALL WORK?

The main power from the battery comes into the unit via the 120A fully sealed SurLok connector. A 4 pin Deutsch DTP connector houses 4 x 25A high or low side switching outputs. Each of these 4 pins is capable of supplying up to 25A of current. The 25A HCOs (High Current Outputs) can be pulsed width modulated at speeds of up to 1khz, or 1000 times per second, which makes them capable of doing speed control on thermo fans or fuel pumps straight out of the box.

NOTE: The 25A rating is the limit of the Deutsch DTP pin being used, not the limit of the driver internal to the PD16 unit which means these pins can actually supply significantly more than 25A for short periods of time.

A 34pin Superseal connector houses 10 x 8A high side outputs. These outputs can supply up to 8A of continuous current on each output. There are also 2 x 8A high/low push-pull, H-bridge outputs that can be used for DC motor control like Varex variable exhaust flaps.

The 8 programmable inputs on the 34-pin connector can be used as analog voltage inputs for pressure and temperature sensors, 4 of these inputs are also capable of accepting high-speed switched inputs for things like wheel speed inputs and frequency-based flex fuel sensors.

A 5V sensor supply and a signal ground for powering up any sensors that will be wired into the PD16 is also on the 34-pin connector.

The PD16 is directly integrated with the NSP software so any sensors, inputs or outputs wired into the PD16 are automatically and instantly available for ECU functions as well. So it is, for example, possible to set a boost trim based on whether your headlights are on or off.

Each output channel has its own LED status indicator light. If the LED isn’t lighting up it means the channel is off. If it lights up green – the channel is on and operating correctly. If the LED is showing as red then the channel is in a “Fault” state, usually caused by an overcurrent.