Home
/
Shop
/
Bolec EM301 Multi-Input Engine Monitor – Electronic Fail-Safe Watchdog for Diesel Engines, Boats, Buses & Heavy Equipment

Sale!

Bolec EM301 Multi-Input Engine Monitor – Electronic Fail-Safe Watchdog for Diesel Engines, Boats, Buses & Heavy Equipment

Bolec EM301 Multi-Input Engine Monitor – Electronic Fail-Safe Watchdog for Diesel Engines, Boats, Buses & Heavy Equipment

Name: Bolec EM301 Multi-Input Engine Monitor – Electronic Fail-Safe Watchdog for Diesel Engines, Boats, Buses &amp; Heavy Equipment
Brand: Bolec
SKU: BEM302-2
Price: 520.00 AUD
Availability: BackOrder

Original price was: $580.00.Current price is: $520.00.

Available on backorder

Add WL601P Probe

Add Extra WL601 Probe (+$20.00)

WL601P Water Level Probe

Product price:	$520.00
Total options:
Order total:

Available to order Bulk order pricing Delivery information Need help? 0480 312 400

EM301 Compact Multi-Input Engine Monitor — a 12/24VDC electronic
watchdog that monitors six engine or machine fault inputs, delays protection during
starting, then provides audible / visual warning and automatic shutdown.

6 monitored inputs
12/24VDC operation
Startup delay
Automatic shutdown
Stored fault indication
115 × 90 × 56mm

Suitable for trucks, buses, boats, agricultural equipment, stationary engines,
pumps, generators and compressors. A practical
Murphy 09PWP12V02 Watchdog alternative for suitable applications
after wiring, sensors, shutdown logic, gauges and enclosure requirements are verified.

View the complete overview ↓
·
Compare with Murphy

BOLEC Gauge & Sender Selector

Search by keyword, thread size or SKU, or choose a filter. Compare up to three products.

Compatibility note

This selector narrows products by stated specifications only and does not confirm direct compatibility. Water gauge: 291.4–22.4 Ω; water senders: 291.5–22.4 Ω. Oil temperature gauge: 316–19 Ω; oil temperature senders: 361–19 Ω. The 0–5 bar oil pressure gauge and 0–10 bar pressure sender use different pressure ranges. Confirm the complete calibration and installation requirements before ordering.

Search by keyword / SKU

Try:

Application

Part type

Thread size

Measurement range

No products shown yet.Choose a filter above or enter a keyword / SKU to see matching products.

Product resources

Request datasheet Request manual Technical support

EM301 overview

Compact six-input engine protection for space-sensitive installations

The EM301 is Bolec’s compact electronic engine watchdog for trucks, buses, boats, agricultural machinery, stationary engines, pumps, generators and compressors. It monitors six connected fault inputs, delays protection during starting, then provides audible / visual warning and automatic shutdown when a valid fault is detected.

Six engine or machine protection inputs
12/24VDC negative-ground operation
Startup delay prevents nuisance shutdown while starting
Fail-safe input design helps identify wiring faults or disconnections
Fault indication retained in memory after detection
Compact module for OEM and retrofit installations

A4 product summary — print or save as PDF. Print this page

Operating sequence

How the EM301 protects the engine

The complete operating sequence is kept together so the product is easy to understand before installation.

Key switched ONThe output relay energises and the starting sequence begins.
Startup delayInput monitoring is temporarily bypassed while oil pressure and charging conditions stabilise.
Monitoring activeThe six connected protection inputs are monitored during normal operation.
Fault detectedThe audible alarm and the relevant LED indication activate.
Shutdown and memoryThe shutdown output operates and the detected fault condition is retained for diagnosis.

Installation note:The final engine stop method depends on the connected fuel solenoid, stop circuit, sensor switches and wiring. Installation and commissioning should be completed by a suitably qualified automotive, marine or industrial technician.

Protection inputs

What the EM301 monitors

All six inputs are shown in one table so the standard functions and spare channels are easy to find.

Oil pressure	Connects to a suitable normally-open or normally-closed oil-pressure switch.
High engine temperature	Connects to a suitable normally-open or normally-closed engine-temperature switch.
Alternator failure	Monitors the charging-system input so alternator or drive-belt failure can initiate warning and shutdown.
Loss of coolant water	Provides a dedicated input for a compatible coolant-level protection circuit.
Spare input 1	Normally-open or normally-closed input for an additional engine or machine protection condition.
Spare input 2 / pump loss of prime	Normally-open or normally-closed input commonly used for pump loss-of-prime protection.

Fail-safe input supervision:The published EM301 design is intended to detect wiring faults or disconnected input circuits as well as genuine monitored faults. Confirm the required switch polarity and circuit arrangement during commissioning.

Fault indication memory

Identify the detected fault after the engine has stopped

When a monitored fault is detected, the EM301 activates the audible alarm and LED indication, operates the shutdown output and retains the fault condition in memory. This helps the operator or technician determine which protection input caused the shutdown instead of relying on guesswork after the engine has stopped.

Stored fault indication

Review the fault that caused shutdown
Assist diagnosis after an intermittent event
Check protection inputs during commissioning

Murphy 09PWP12V02 Watchdog comparison

EM301 vs Murphy 09PWP12V02 engine protection panel

The EM301 can be a practical Murphy Watchdog alternative where a compact electronic monitor is preferred. It is not a direct or pin-for-pin replacement for a complete Murphy gauge panel, so selection must be based on function, wiring, sensors, shutdown logic and enclosure requirements.

Selection point	Bolec EM301	Murphy 09PWP12V02 Watchdog
Product format	Compact electronic monitoring and shutdown module	Weatherproof engine protection panel with mechanical Swichgage instruments
Published monitoring	Oil pressure, high temperature, alternator failure, coolant loss and two spare inputs	Oil pressure and engine temperature Swichgage instruments
Automatic shutdown	Yes — electronic relay output	Yes — Murphy 518 shutdown relay
Fault indication memory	Yes — detected fault condition is retained	No fault-memory function is listed in the published 09PWP12V02 feature set
Operator instruments	No analogue gauges are listed as part of the EM301 module	Oil-pressure and water-temperature Swichgage instruments
Enclosure	Compact 115 × 90 × 56mm module; installation enclosure to suit the application	Published as an IP56 weatherproof panel
Replacement guidance	Do not assume a direct replacement. Verify supply voltage, switch and sensor types, shutdown circuit, relay loading, required gauges, mounting dimensions, environmental protection and supplied wiring before changing panel type.

Murphy and Swichgage names are used for product identification and application comparison. Specifications can vary by panel configuration.

Published product data

EM301 specifications

Model	EM301
Product type	Compact multi-input electronic engine monitor and automatic shutdown module
Supply	12/24VDC, negative ground
Monitored inputs	6
Current draw	100mA at 24VDC, no load
Relay rating	10A resistive at 24VDC
Published dimensions	115 × 90 × 56mm
Installation type	OEM and retrofit installations
Country of manufacture	Australia

Typical applications

Trucks and buses
Marine engines
Agricultural tractors and equipment
Stationary engines and pumps
Generators and compressors

Included connection hardware

1 × 4-way male terminal block
1 × 6-way male terminal block
10 × brass terminals

An additional WL601P coolant-level probe can be selected from the product options where required.

Best suited to EM301

Space is limited.
Six switch-type protection inputs suit the engine.
Automatic shutdown and stored fault indication are required.
Separate analogue gauges are not required in this module.

Commissioning checks

Confirm each input function and N/O or N/C switch arrangement.
Confirm the shutdown circuit and connected relay load.
Test the startup delay and every protection condition.
Confirm that the correct fault indication remains available after shutdown.

Watch the Bolec engine protection panel video

The controlled EM301 instruction manual and the markings on the supplied product take precedence.

Frequently asked questions

EM301 selection and replacement questions

Is the EM301 a direct replacement for a Murphy 09PWP12V02 panel?

No direct or pin-for-pin replacement is claimed. The EM301 is a compact electronic monitor, while the Murphy panel includes mechanical pressure and temperature instruments in a weatherproof enclosure. Check every function, sensor, connection, shutdown load and enclosure requirement before replacement.

What happens during the startup delay?

The monitored fault inputs are temporarily bypassed while normal oil pressure and charging conditions develop. Monitoring then becomes active for normal running.

Can the spare inputs be used for other machine faults?

The product information lists two spare normally-open or normally-closed inputs. One is commonly used for pump loss of prime. Final suitability depends on the switching circuit and required shutdown logic.

Does the EM301 remember which fault caused the shutdown?

The published operating sequence states that the detected fault condition is stored in memory when the alarm and LED activate. Refer to the controlled manual for the exact reset and review procedure.

Is a coolant-level probe included?

The standard connection hardware is listed separately. An additional WL601P coolant-level probe is available as a selectable product option where required.

Documents and support

EM301 instruction manual and application assistance

View EM301 Instruction Manual Installation, wiring, operation and controlled product information. Technical and replacement support Ask about input switches, wiring, shutdown logic, relay loading or Murphy Watchdog suitability.