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Engines & Power Equipment / Australian Control Systems Since 1978

Engine protection you can choose, wire and prove with confidence.

Select a standard BEM panel and buy online, or tell us how your engine is wired and have the panel configured for the job. Clear 12/24VDC circuits, no software to program, and a fault-by-fault test process that makes sense at the machine.

No laptop requiredInstaller-friendly pin scheduleEvery BEM panel is customisableStandard and 24V options
Choose my panel I need a modified panel
Standard panelChoose → Buy → Install → Test
Modified panelSend details → Confirm scope → Build → Install

Choose In Under 30 Seconds

Start with what the engine actually needs.

These three panels use the same easy-to-understand protection idea. The difference is how much instrumentation and application-specific monitoring you need.

Basic Engine Protection PanelEssential protection

BEM302

Basic Engine Protection Panel

Best for

Engines that already have gauges, or installations that mainly need reliable warning and shutdown protection.

Choose this when

You want the simplest panel in the range with four dedicated engine faults and two configurable spare inputs.

Monitors
Oil pressure / high temperature / alternator / coolant
Install approach
Straightforward protection-focused wiring
Customisable before deliverySpare-input functions, sender logic, coolant setup and 24V configuration can be modified.
View & buyAsk about modification
Industrial Engine Protection PanelComplete industrial panel

BEM502

Industrial Engine Protection Panel

Best for

Generators, pumps, compressors and stationary engines that need instrumentation and protection in one panel.

Choose this when

You need tacho, temperature and pressure-gauge connections as well as the six-input watchdog.

Monitors
Oil pressure / high temperature / alternator / coolant
Install approach
12-pin connector with gauge and switch circuits
Customisable before deliverySpare inputs, sender logic, coolant monitoring and 24V configuration can be modified.
View & buyAsk about modification
Irrigation Engine Protection PanelPurpose-built for irrigation

BEM502IRN

Irrigation Engine Protection Panel

Best for

Remote irrigation and pump engines where loss of prime or belt failure must be treated as a real shutdown fault.

Choose this when

You want dedicated pump and belt inputs instead of two general-purpose spare inputs.

Monitors
Pump / oil pressure / temperature / alternator / coolant / belt
Install approach
Familiar BEM502-style connector and controls
Customisable before deliveryPump and belt logic, sender type, coolant setup and 24V configuration can be modified.
View & buyAsk about modification
Need protection only?BEM302
Need gauges and protection?BEM502
Need pump and belt faults?BEM502IRN
Engineered in AustraliaIndustrial control experience since 1978
Simple switched inputsOil, temperature, D+, coolant and application faults
Built to be testedStart delay, first-fault indication and history recall
Built to be modifiedVoltage, sender logic, inputs, coolant and fault response

Explore The BEM Family

The model code points you to the right panel.

Go beyond the three core panels when the machine is water-cooled or needs dual-pressure or voltage monitoring. Select a family below to compare the confirmed variants.

Application-specific 502 models

When the standard panel needs one more job.

These variants keep the familiar BEM protection logic and add monitoring for a specific machine requirement.
Dual-Pressure Irrigation PanelDual pump pressure

BEM502IRN DP

Dual-Pressure Irrigation Panel

Best for
Irrigation or stationary diesel systems that must prove two separate pump-pressure circuits.
Monitors
Pump 1 / Pump 2 / oil / temperature / alternator-belt / coolant
Adds two Murphy pump-pressure gauges, automatic shutdown, adjustable start delay, audible alarm and first-fault memory.View model
Voltage-Monitoring Engine PanelBattery + charge voltage

BEM502VM

Voltage-Monitoring Engine Panel

Best for
Industrial engines where battery condition and charging voltage need to be visible with engine protection.
Monitors
Voltage / oil / temperature / alternator / coolant / auxiliary fault
A compact IP56 12–24VDC configuration with dual outputs, audible warning and stored first-fault indication.View model
2

Standard engine familyThe familiar BEM502 configuration.

3

Water-cooled familyThe final digit changes for the water-cooled model.

IRN

IrrigationPump and belt protection for irrigation engines.

DP / VM

Special monitoringDual pressure or battery/charge voltage monitoring.

Still comparing?

See the complete Bolec engine-protection range.
View all products

Installation Confidence

Can I install it myself?

If you can safely work on 12/24VDC equipment, read a pin schedule, make sound crimps and use a multimeter, the installation should feel familiar. No coding, app or laptop is involved.

Likely within your skill set

A capable owner-installer or apprentice technician can:

  • Safely isolate and test a 12/24VDC circuit
  • Read a pin number, wire colour and function table
  • Crimp, heat-shrink, label and inspect connections
  • Identify a switch opening or closing to ground
  • Simulate a fault and verify the correct response

Pause and bring in an Auto Elec or Diesel Fitter

Get help when the machine side is uncertain:

  • Fuel or stop-solenoid type and current draw are unknown
  • Existing starter wiring or isolation is unclear
  • Sender logic cannot be identified as N/O or N/C
  • The engine is 24V but the panel has not been configured
  • The shutdown forms part of a regulated safety function

What comes in

Battery + / GroundIgnition / StarterOil / Temp switchesAlternator D+Coolant / Pump / Belt
12/24VDC ENGINE WATCHDOGBEM PANELDelay + Input Logic + Fault Memory

What comes out

Audible warningFault LEDFuel relay actionShutdown responseRecallable fault history
01

Choose the panel

Match the application first: basic engine protection, a complete industrial panel, or an irrigation-specific panel.

02

Confirm the electrical system

Identify 12V or 24V, negative ground, fuel or stop-solenoid type, sender switching and the required shutdown action.

03

Mount and connect

Mount the panel where it remains serviceable, then connect power, ground, ignition, starter, gauges and switches to the pin schedule.

04

Set the input logic

Set the DIP switches for normally-open or normally-closed senders. Enable coolant monitoring only when the correct probe is fitted.

05

Prove every fault

Run through the start delay, simulate one fault at a time, and confirm the alarm, indication, relay or shutdown response before service.

Typical BEM502 / BEM502IRN Connector

Four wire groups make the 12-pin connector easier to read.

This is an installer-level overview, not a substitute for the model manual. BEM302 leaves some instrument pins unused. Always verify the supplied panel and harness before wiring.

Power & start
7 Yellow
Ignition
8 Black
Ground
10 Red
Battery +V
12 Violet
Starter solenoid
Engine switches
4 Brown thin
Temperature switch
6 Blue thin
Pressure switch
Auxiliary faults
2 Red / White
Alternator / charge
9 Grey thin
Spare / water level
11 White thin
Spare / belt break
Instruments
1 Grey
Tacho
3 Brown
Temperature gauge
5 Blue
Pressure gauge
Three installation details that prevent most confusion
1. Fit the specified 10A inline fuse and confirm a clean ground.2. Keep sensor wiring away from motors, solenoids and ignition wiring.3. Put every unused failsafe input into the documented healthy state.

Modified To Suit The Machine

Every BEM panel can be configured or modified.

You do not need to force the machine to fit a standard panel. Tell Bolec what voltage, senders and fault response you have, and confirm the modification scope before the panel is supplied.

01

12V or 24V configuration

The standard setup is 12VDC. A 24VDC unit requires internal configuration, so specify voltage before ordering.

02

Sender input logic

Inputs can be matched to normally-open or normally-closed switches to ground using the panel DIP settings.

03

Coolant-level monitoring

The coolant input can be enabled for a suitable single-conductor probe, or used with an interface for many multi-wire probes.

04

Application fault inputs

BEM302 and BEM502 spare inputs can be adapted to application faults. BEM502IRN is already arranged around pump and belt protection.

05

Harness and installation package

Select a breakout or longer harness and confirm wire functions, labels and connection details before the panel reaches the machine.

06

Fault response

Discuss the desired warning, fuel-relay or shutdown behaviour so the final panel arrangement suits the engine and operating risk.

For A Fast Recommendation

Send these five details.

  • Engine or machine model and what it powers
  • 12V or 24V negative-ground system
  • Available oil, temperature, coolant and alternator signals
  • Desired warning and shutdown behaviour
  • Photos of the existing panel, harness and engine senders

Not sure how to describe the sender logic? Clear phone photos of the sender, existing panel and wire labels are useful.

Request a modified panel

What Happens When You Turn The Key

The protection sequence is automatic and visible.

The panel does the timing and monitoring. The installer only needs to wire the correct inputs, select the correct logic and prove the required response.

01

Relay energises

The fuel-solenoid output is energised for engine operation.

02

Start delay runs

Sensor circuits are bypassed while the engine starts and stabilises.

03

Inputs become active

The selected engine and application faults are continuously monitored.

04

First fault is held

The audible warning and matching LED identify the fault that occurred first.

05

History can be recalled

Recent shutdown causes can be reviewed to make field diagnosis faster.

Applications

One understandable protection platform across many engines.

Use a complete panel, a compact monitor or an installation harness to suit a new build, retrofit or replacement.

01Irrigation pumps
02Generators and power packs
03Agricultural machinery
04Marine engines
05Trucks and buses
06Compressors and stationary plant
07OEM and retrofit panels
08Remote unattended engines
View all products

Before You Buy

Common installation and selection questions.

Can I install a BEM panel myself?

A competent person who can safely work on 12/24VDC equipment, read a pin schedule, make reliable crimps and test switch inputs with a multimeter should find the wiring approachable. Use a qualified Auto Electrician or Diesel Fitter when the machine-side starter, stop-solenoid or sender wiring is uncertain.

Do I need software or a laptop?

No. BEM panels use physical wiring, DIP-switch input logic and a coolant jumper. Commissioning is completed by checking the start delay and proving each required fault.

What is the difference between BEM302 and BEM502?

BEM302 is the simpler protection-focused panel. BEM502 adds tacho, temperature and pressure-gauge connections for a more complete industrial engine panel.

Which panel is best for an irrigation pump?

BEM502IRN is arranged around irrigation engines, with dedicated pump and belt fault inputs as well as oil, temperature, alternator and coolant protection.

What do BEM503 and the other model suffixes mean?

The final 3 identifies the water-cooled family: BEM503 is the water-cooled counterpart to BEM502, and BEM503IRN is the water-cooled irrigation version. IRN identifies irrigation, DP adds dual pump-pressure monitoring, and VM adds battery and charge-voltage monitoring.

Can the panels be modified?

Yes. All three BEM panels can be configured or modified to suit the application. Common areas include 24V operation, sender logic, coolant monitoring, spare or dedicated inputs, harness requirements and the required fault response.

Can the panel monitor low coolant level?

Yes. Coolant monitoring is disabled at the factory and can be enabled for a suitable single-conductor probe. An interface may be required for a two- or three-conductor resistive probe.

What should I test before returning the engine to service?

Confirm polarity and ground, the start-delay sequence, every connected fault input, the matching LED and alarm, the intended relay or shutdown action, and the fault-recall function. Test one fault at a time.

Standard Or Modified

Choose the closest panel, then decide how you want to buy.

Ready to install a standard panel?Choose & buy
Want to compare every standard and derived model?View all products
Need voltage, inputs or logic changed?Request a modified panel
Prefer to talk? Call 0480 312 400
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