Monitoring and switching on board
P-BUS: the on-board electrical system by philippi
The P-BUS is a communication network based on CAN bus that philippi has adapted to the requirements of power supply and battery monitoring. Batteries, tanks, temperatures, charging sources, AC system and consumers come together on one or more system monitors – and can be switched from there as well.
How the P-BUS is structured
At its centre are the system monitors PSL and PSM 3. They display all data arriving via the P-BUS and also serve as the control panel. Several monitors can be installed at different locations on board and queried independently of each other.
Monitoring
Shunt SHX for the battery, tank interface CMT 3, temperature interface TPC 4, relay module CMR for the bilge pump.
Energy
ACE chargers, DCB charge boosters, SCE solar controllers and DCW inverters deliver their data directly; everything else is captured by shunt SHX-L (DC) or interface CAV (AC).
Switching
Main switches via circuit breaker FHC 265 and interface TSC, consumer circuits via the CMR relay modules – with dimming for LED lights.
Communication
Bridge CBN to NMEA 2000, interfaces to Studer Xtender, Mastervolt and SuperB, Smart Interface for the philippi app.
Wiring and set-up
- M12 connectors: Since 2013 philippi has connected the P-BUS components with the waterproof M12 system (DeviceNet). Each interface comes with a T-adapter cable; only the connecting cables between the devices are needed.
- Set-up on the monitor: After installation the devices are registered once on the system monitor. No configuration software or PC is required.
- Energy-saving mode: When all system monitors are in standby or switched off, the connected components also go into energy-saving mode.
- Open system: The installation starts with a single shunt SHX and grows into a digitally switched on-board system without existing components becoming obsolete.
Important: The P-BUS is not an NMEA 2000-certified system. It uses the same cables but may only be coupled to an NMEA 2000 network via the NMEA 2000 Bridge CBN.
The P-BUS components at a glance
| Component | Task | Key technical data |
|---|---|---|
| System monitor PSL | Central display and control | 5" touchscreen, 8–32 V DC, 90 mA (standby 10 mA), panel cut-out 140 × 85 mm |
| System monitor PSL plus | as PSL, with integrated tank interface | 4 tank senders and 2 temperature sensors directly on the monitor |
| System monitor PSM 3 | Central display and control | 3.5" touchscreen, 8–64 V DC, 60 mA (standby 2 mA), panel cut-out 88 × 88 mm |
| Battery management shunt SHX 348 | Current, voltage, capacity of the battery | 300 A (600 A 1 min, 1500 A 0.5 s), 8–64 V, M8 stud |
| Battery management shunt SHX 648 | for higher currents | 600 A (800 A 1 min, 2500 A 0.5 s), 8–64 V, M16 stud |
| Current measuring shunt SHX-L 300 | Charging source or consumer without P-BUS | 300 A, 8–32 V, M8 stud |
| Tank interface CMT 3 | up to 4 tank senders | 10–180 Ω, 240–33 Ω, 4–20 mA, 0–5 V, ultrasonic, flow |
| Temperature interface TPC 4 | up to 4 temperature sensors | Temp-BT or Temp-HT, up to four TPC 4 per P-BUS |
| AC interface CAV | one AC phase 230 V / 50 Hz | 16 A internal, 100 A with current transformer WAC 100 |
| Relay modules CMR | Switch, dim and monitor consumers | 2 to 8 channels, 10 A or 30 A per channel, single- or double-pole, emergency mode |
| Circuit breaker FHC 265 | remote-controlled battery main switch | 12 + 24 V, 260 A continuous current, adjustable deep-discharge protection; bipolar version 2 × 260 A |
| Main switch interface TSC | controls the isolator FBR 500 | for continuous currents up to 500 A |
| NMEA 2000 Bridge CBN | P-BUS data for chart plotters | PGN 127501, 127505, 127506, 127508, 127744, 127747, 127750 |
See also: PCU Control Unit · Digital switching · Academy: the networked on-board system
P-Bus Battery Management Shunt SHX 348
P-Bus Battery Management Shunt SHX 648
P-Bus Temperature Interface TPC 4
P-Bus Relay Module CMR 411 S
P-Bus Relay Module CMR 811 S
P-Bus Relay Module CMR 431 S
P-Bus Relay Module CMR 412 S
P-Bus Relay Module CMR 232 S
Remote-controlled P-bus circuit breaker FHC 265
Remote-controlled P-bus circuit breaker FHC 265 Bipolar
Frequently asked questions about the P-BUS
What is the P-BUS?
The P-BUS is a communication network based on CAN bus that philippi developed for power supply and battery monitoring on board. Monitors, shunts, interfaces and switching modules exchange their data over it. Because the network runs permanently, it is designed for low self-consumption: when all monitors are in standby, the connected devices also switch to energy-saving mode.
Is the P-BUS compatible with NMEA 2000?
The P-BUS uses the same M12 connectors as NMEA 2000, so NMEA 2000 cables fit as well. However, it is not an NMEA 2000-certified system and must not be connected directly to an NMEA 2000 network. Coupling is done via the NMEA 2000 Bridge CBN, which converts battery, tank, switching and AC data for chart plotters.
Do I need a computer for set-up?
No. The P-BUS devices are registered and configured directly on a PSM 3 or PSL system monitor; no additional PC is required. After installation, the connected devices are registered once. Settings such as tank size, sensor type, alarm thresholds or deep-discharge protection are then also made on the monitor.
Where do I start with the P-BUS?
The smallest sensible configuration is a system monitor with an SHX battery management shunt. With an additional CMT 3 tank interface, the basic functions for battery and tanks are available. Temperature, AC monitoring, main switches and digital switching can be added later without replacing existing components.
Which devices from other manufacturers can be integrated?
Dedicated interfaces bring data from other systems into the P-BUS: Studer Xtender via the XCOM-CAN bridge, Mastervolt devices via the CMB interface, SuperB batteries via the CBO-SB interface and Victron combi inverters via the Smart Interface. Sources and consumers without a P-BUS connection are captured by the SHX-L current shunt or the CAV AC interface.
What happens if the P-BUS fails?
The CMR switching modules have an integrated emergency mode: each output can be bridged by repositioning the fuse or circuit breaker and remains protected. For the remote-controlled main switches, philippi also recommends a control button so they can be operated independently of the P-BUS.
Technical data according to philippi catalogue No. 26, P-BUS chapter (pp. 26–37).
