TECHNICAL ARTICLE
EPM900
The Module that Protects and Powers the Heart of Your Electric Vehicle
What is a power management module really for—and why it matters in EV design
When designing an electric traction system, it’s not enough to have a good battery and motor. You also need an intelligent module that can:
- Safely activate the power circuit,
- Protect inverters and sensitive components,
- Deliver clean auxiliary power, and
- Communicate with the vehicle system using standard protocols.
This is the purpose of EPM900, a compact module developed by FACOS that acts as the auxiliary brain for energy distribution and safety in electric vehicles.
EPM900: 3 Key Functions in One Compact Unit
1. DC-DC Converter
- Converts 48–80 VDC to a 14.7 V nominal output (adjustable via CAN from 13.5 V to 15.5 V)
- Output current adjustable up to 100 A (default: 80 A)
- Powers 12V systems like lighting, GPS, fans, sensors
- Includes active galvanic isolation
- Actively cooled with top-mounted fan
2. Smart Pre-Charge + Safety Interface
- Stabilizes voltage before full system activation
- Prevents dangerous inrush current to inverters and drives
- Includes electronic interlock: detects disconnection and safely shuts down the HV circuit
3. Communication & Diagnostics
- CAN-Bus (J1939, connector J1) for in-vehicle integration
- RS-485 for PC-based diagnostics and configuration
- Compatible with FACOS software and custom browser tools
Advanced Technical Specifications
| Parameter | Value / Description |
|---|---|
|
Input Voltage |
43 – 80 VDC |
|
DC-DC Output Voltage |
Adjustable 13.5 – 15.5 V (default 14.7 V) |
|
DC-DC Output Current |
Up to 100 A (default 80 A) |
|
Cooling |
Active, fan-assisted |
|
Galvanic Isolation |
Active |
|
Pre-charge Logic |
Embedded, automatic |
|
Interlock System |
Electronic, configurable |
|
Protection |
Overvoltage, overcurrent, thermal |
|
Communication |
CAN-Bus (J1939), RS-485 |
Why Is It Indispensable?
When starting an EV, current flows rapidly from battery to drive.
Without a module like the EPM900:
- Inverter capacitors can be damaged
- Voltage spikes may occur
- Startup can fail or behave unpredictably
With EPM900:
- Smooth and safe power-up
- Reliable system behavior
- Longer lifespan of electronic components
Easy Integration, Maximum Reliability
- Plug & play compatible with all FACOS systems
- Installable even in tight spaces
- Designed for harsh environments (IP67 rating)
- Monitorable via PC browser or FACOS software
Already deployed in over 800 professional electric vehicles across Europe.
Typical Applications
- Electric and hybrid tractors
- Advanced professional cargo bikes
- Electrified marine platforms
- Utility and municipal EVs
- Custom off-road or industrial EV systems
Planning an electric vehicle and want to avoid startup or power instability issues?
Integrate the EPM900 and rely on a power management solution designed for long-term performance.