Power distribution module

PDM28

Q: What is a PDM?

A PDM (Power Distribution Module) replaces the conventional relays and fuses in a vehicle electrical system. It takes inputs from physical switches, analogue voltages or the CAN bus, and powers the attached loads such as radiator fans, lights and pumps. The current drawn by every load is continuously monitored. If it gets too high because of a fault, the PDM switches that output off to protect the wiring loom and the device, then retries it to see if the fault has cleared. Solid state technology means maximum reliability without the drawbacks of mechanical relays and fuses. Vibration, water and dirt are no longer a problem.

Q: Can it replace my fuse box and relays?

Yes. Every output is switched and protected electronically, with its own Low, High and Peak fuse thresholds, automatic retries and a thermal limit, so separate fuses and relays are no longer needed.

Q: Will it work with my ECU?

If your ECU sends data over CAN, yes. Import its DBC file and the PDM creates the matching inputs automatically; DBC import covers all major ECU brands. The PDM can also send its own data back as a predefined CAN stream.

Q: Which keypads can I use?

Up to four CAN keypads at once: Blink Marine CANopen (4 to 15 buttons, including dial versions and the Race Pad), Grayhill and Motec CANopen (6 to 20 buttons) and the Marlin J1939 8-button keypad.

Q: How do I set it up?

Connect it to a Windows PC with the supplied USB cable and use the free configuration software; no programmer is needed. You can also build configurations offline, and connect over CAN with a Kvaser interface.

Q: Is it waterproof?

Yes. It is IP67 water and dust resistant, and works from -55 °C to 90 °C.

Our flagship module, the product of over three years of development and testing. 28 high/low side outputs in a machined aluminium enclosure with 50 RGB status LEDs.

Buy from £1,445.00 Manual (PDF)

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Why the PDM28

28 outputs, 200 A

4 × 30 A and 24 × 20 A high/low side outputs, each with current measurement and fully programmable fusing.
3 × CAN plus LIN

Talk to ECUs, keypads and OEM modules: DBC import and export, custom messages, a J1939 stream and a LIN master.
Logic, scripts and tables

Logic functions, maths channels, timers, 2D tables and on-device scripts, all set up in free software.
Built to survive

Machined aluminium, IP67, -55 °C to 90 °C, with a 9-axis IMU for rollover and impact cut-off and 128Mb of logging.

Technical specification

Features

General

Size: 318 × 124 × 58 mm.
Weight: 1640 g.
Operating voltage: 12/24V (4V to 32V).
Quiescent current draw: 4 to 5 mA. Operating: 350 mA @ 12V, 250 mA @ 24V.
Operating temperature: -55°C to 90°C (-67°F to 194°F).
Construction: machined aluminium, media blasted and anodised black.
IP67 water and dust resistant.
Connectors: 2x DTM 12-pin, 2x DT 12-pin, 1x DTP 4-pin, quick-release Radlok power connectors.
Update rate up to 2000Hz.
50x RGB LED indicators.
USB connection to a Windows PC, no external programmer required. Free configuration software.

Inputs

16x analogue inputs, which can also serve as digital inputs.
Measurement range 0 to 28V, independent of battery voltage.
Resolution: 16-bit (0.001V).
Protected from -24V to 40V.
Software-selectable 10K pull-up/down resistors for positive or ground switching.
Momentary or latched, active high or active low, with configurable hysteresis.
Turn-on delay (debounce) and an adjustable filter, previewed on a live threshold graph.
Frequency measurement up to 300Hz with automatic triggering.

Outputs

4x high/low side, reverse current blocking outputs: 30A continuous (pin-limited to 25A @ 125°C), 100A peak.
6x high/low side, reverse current blocking outputs: 20A continuous (pin-limited to 13A @ 125°C), 80A peak.
18x high/low side outputs: 20A continuous (pin-limited to 13A @ 125°C), 80A peak.
200A combined maximum output current. Current measurement resolution 3mA.
Output voltage measured on every output.
Automatic output current trip threshold tuning.
Each output is overcurrent, overtemperature, load dump and reverse polarity protected.
Output current control in 100mA steps.
Peak and High fuse thresholds with a peak time allow for inrush current. A live fuse graph shows the settings against an example load.
Under-current (Low Fuse) detection finds open circuits and failed loads.
Per-output thermal shutdown limits, so non-critical loads shut down first.
Trip mode: Instant (trips as soon as the threshold is exceeded) or Normal (behaves like a physical fuse and allows short spikes).
Turn-on delay, and stay-on time after the input is removed, useful for radiator fans and water pumps.
Automatic retries after a trip: 1 to 9 times or indefinitely, with a set clear time.
PWM from 100Hz to 1000Hz on each output, with soft start and duty cycle mapped to any live variable.

Functions

Each output can be switched by a user-defined logic function of up to 12 conditions, or follow another output.
Logical operators: AND, OR, NOR, XOR, NAND, >, >=, <, <=, Equal, Not Equal.
Global Cut Off turns off every output at once, for example on an emergency stop, low voltage or an IMU impact.
Global Reset re-enables any tripped outputs in real time.
30 Generic Functions hold reusable logic that outputs, timers, counters and keypads can share.

Scripting

Write your own logic in a simple JavaScript-style language, compiled and run on the PDM.
Up to 5 scripts, each with 10 published values and 16 bindings to live PDM data.
State kept between loops, arrays, helper functions, maths and bitwise operators, and timing with dt, sleep and yield.
Scripts can set counters and keypad button states, and transmit raw CAN frames.
Script values can be used anywhere: output logic, CAN outputs, logging and more.
Live variable inspector with history, and faults reported against the exact source line.
Built-in examples: thermostat with hysteresis, PID control, debounce, soft start, amp-hour counting and CAN CRC fault handling.

Maths Channels

30 real-time maths channels convert data on the fly.
Basic: addition, subtraction, multiplication, division, modulus.
Bitwise: AND, OR, XOR, left shift, right shift.
Advanced operations: Choose, Min, Max, Sin, Cos, Tan, Floor, Ceil, Abs, Asin, Acos, Ln, Log, Pow, Sqrt.
30 counters that count up, count down and reset on rising-edge conditions, with optional loop-around.

Sensor Calibrations

10 calibration curves of up to 20 points convert raw voltages or CAN values into real units.
Linear interpolation between points, edited on a live graph.
Use calibrated values anywhere: output logic, CAN, logging, tables and scripts.

2D table 3D view in the PDM configuration software

2D table grid view in the PDM configuration software

2D Tables

5x 20 × 20 tables map two variables to one output, for example fan duty from coolant temperature and road speed.
Vertical, horizontal and 2D interpolation with keyboard shortcuts.
3D surface view, with the live operating point traced on the table.

Pulse train timer in the PDM configuration software

Duration timer in the PDM configuration software

Timers

30x timer channels.
Pulse trains with set on and off times, for example for indicators.
Duration timers started by a condition, with automatic or conditional reset.

CAN Bus

3x CAN 2.0A/B: CAN 1 and CAN 2 for your devices, CAN 3 reserved for NIO power module expansion.
Bus speed: 50, 100, 125, 250, 500, 1000 kbps. Software-selectable termination resistors.
100 CAN inputs with 20 hardware filters, bit masking, scaling/offsetting, timeout with default value and compound message filtering.
CRC-8 (SAE J1850) and rolling counter checks on received messages, with error counters for fault handling.
DBC file import creates the inputs and filters automatically, for all major ECU brands.
100 custom CAN output messages with up to 32 signals each: 1 to 32-bit signed or unsigned values, flags or floats, either byte order, at any bit position.
Periodic (1Hz to 50Hz) or event-triggered transmission, with optional rolling counter and CRC.
Predefined CAN output stream of PDM data, standard or J1939 Proprietary B. DBC export for the stream and your own messages.

LIN Bus

1x LIN bus with the PDM as master.
Import and export LDF files. Nodes, signals, encodings, frames and schedule tables are created automatically.
Up to 16 slave nodes, 50 signals and 20 frames, with a visual frame packing editor.
Send any PDM variable to LIN devices and use received LIN signals anywhere in the configuration.
Control and communicate with OEM sensors and actuators such as electric water pumps.
Live checksum, overrun and byte error counters.

CAN Keypad

Control the PDM from up to 4 CAN keypads with up to 20 buttons each.
Supported: Blink Marine CANopen 4 to 15 button (including the 15 button and PKP2300-MT 6 button with rotary dials), Blink Marine Race Pad, Grayhill CANopen 6 to 20 button, Motec 6 to 20 button, Marlin J1939 8 button.
Momentary, latching and multi-state (up to 3 states) buttons, with optional hold-to-reset.
LED colour per state, shown only when its condition is true, plus a fault colour, so the LED confirms the load has really switched on.
Searchable library of over 3,000 button icons.
Backlight colour and brightness, with automatic dimming from any variable for night driving.
Rotary dials with configurable range, LED offset and hold-to-turn. Race Pad centre LEDs driven from any variable.
Optional button state memory across power cycles, and a pass key lock that needs a four-button sequence before the keypad will work.
Keypads can be on CAN 1 or CAN 2.

IMU

9-axis IMU: roll, pitch and yaw, plus acceleration and rotation rate on every axis.
Live 3D view of the vehicle and PDM orientation.
Mount the PDM in any orientation: capture vehicle up and forward in the software to set the vehicle reference frame.
Rollover detection with an adjustable maximum safe tilt.
Impact detection with separate positive and negative thresholds on each axis, plus total acceleration, with optional latching.
Rollover and impact triggers can drive Global Cut Off to shut outputs down automatically.

Data Logging

128Mb onboard flash. The oldest data is overwritten when it is full.
Up to 30 logging groups, each with up to 180 variables, a rate from 1Hz to 1000Hz and its own trigger condition.
Live estimate of logging capacity and loop-around time.
Download logs over USB and graph them in the software with multiple graph windows and dual axes, or export to .csv.
Real-time clock with 30-day battery backup for timestamped logs.

Live Data Analysis

View all PDM data in real time, numerically or graphically.
Overview dashboard with dockable panels for outputs, inputs, device summary and keypads.
Multiple live graphs with adjustable time and scale, zoom and .csv export.
Variable groups with sparklines, saved for quick fault finding.
Capture View records short high-speed snapshots, triggered manually or by a condition, with pre-trigger.
Confirm the system is working as intended before deploying the PDM in the vehicle.

CAN Bus Analyser

Fully integrated CAN bus analyser: monitor all traffic in real time, in continuous or fixed (one row per ID) view.
Decode messages with a DBC file.
Log CAN bus data to .csv for external analysis.
Send CAN messages once, periodically, on a trigger or from a keyboard key.
CAN Wizard builds keypad and node commands such as baud rate, node ID and mode.

Diagnostics

Lifetime and resettable short-term statistics stored on the PDM: power-ups, on-time, peak voltage, current, temperatures and IMU values.
Per-output status, trip counts and load as a percentage of the fuse rating.
Configuration Warnings check the setup for common mistakes before you send it.
A configuration check confirms the PC and PDM configurations match.

Configuration Software

Connect over USB, or over the CAN bus with a Kvaser USB-to-CAN interface.
Overview dashboard of every output, input and keypad, plus variable groups with live mini graphs, for fast fault finding.
Offline mode for building configurations without a PDM.
Pin Manager lists every connector pin with its label and exports a printable PDF or interactive HTML pin-out.
Password-lock finished configurations and store installation notes on the PDM.
Undo, copy and paste throughout, with built-in help on every page.
Firmware updates are bundled with the software and installed over USB.

Downloads

Resources

In use

Built with the PDM28

Bearhawk Aircraft

Flight Control Reimagined

PDM28 · CAN Keypads

HCR Innovations

The PDM28 Across Two Generations of Drag-and-Drive Racing

PDM28 · CAN Keypads

All case studies →

Compare

Which PDM do you need?

Feature	PDM28	PDM15/25/35 V2
Outputs	28 (4 × 30 A, 24 × 20 A)	15, 25 or 35 (all 20 A)
High/low side outputs	All 28	4
Combined output current	200 A	120 A
Inputs	16, 16-bit	16, 12-bit
CAN buses	3	1
LIN bus	Yes, master	No
CAN keypads	Up to 4, on CAN 1 or 2	Up to 4
Scripting, tables, maths	Yes	Yes
9-axis IMU	Yes	Yes
Logging	128Mb, 1-1000Hz, real-time clock	128Mb, 1-1000Hz
Status LEDs	50 RGB	No
Power connection	Radlok	M8 stud
Enclosure	Machined aluminium, IP67	Glass-fibre reinforced plastic, IP67
Size	318 × 124 × 58 mm	200 × 160 × 54 mm
Weight	1640 g	645 to 735 g
Approvals	-	UNECE R10.06, FCC Part 15 Class A
Price	From £1,445.00	From £795.00

UK prices exclude VAT.

Questions

FAQ

What is a PDM?

A PDM (Power Distribution Module) replaces the conventional relays and fuses in a vehicle electrical system. It takes inputs from physical switches, analogue voltages or the CAN bus, and powers the attached loads such as radiator fans, lights and pumps.

The current drawn by every load is continuously monitored. If it gets too high because of a fault, the PDM switches that output off to protect the wiring loom and the device, then retries it to see if the fault has cleared.

Solid state technology means maximum reliability without the drawbacks of mechanical relays and fuses. Vibration, water and dirt are no longer a problem.

Can it replace my fuse box and relays?