EM301 Engine Monitor – Compact Watchdog Protection for Critical Engines
The EM301 from Bolec Electronics is our most compact and affordable watchdog engine monitor, designed for space-sensitive installations across trucks, boats, agricultural machinery, and industrial engines. It provides automatic engine shutdown and audible alarms in case of critical faults—protecting equipment from damage and ensuring reliability.
Key Features
- Compact design – smallest Bolec engine monitor
- Monitors oil pressure, coolant level, alternator failure, high engine temperature, and optional inputs
- Fail-safe input design detects wiring faults or disconnections
- Integrated start-up delay and visual/audible alarm with memory
- Relay output: 24VDC / 10A, ideal for solenoid control
- Designed for OEM and retrofit use in limited-space environments
Sensor Inputs
- Oil Pressure (N/O or N/C switch)
- High Engine Temperature (N/O or N/C switch)
- Alternator Failure
- Loss of Coolant Water
- Spare Input 1 (N/O or N/C switch)
- Spare Input 2 – commonly Pump Loss of Prime (N/O or N/C switch)
Operation Sequence
- Key ON: Relay energizes and input monitoring bypassed via delay
- Normal Running: LEDs remain off unless a fault is detected
- Fault Detected: Alarm and LED activate; fault condition stored in memory
Applications
- Trucks and Buses
- Marine Engines
- Agricultural Tractors and Equipment
- Stationary Engines and Pumps
- Generators and Compressors
Specifications
| Dimensions | 115 x 90 x 56 mm |
| Voltage | 12/24VDC, negative ground |
| Current Draw | 100mA @ 24VDC (no load) |
| Relay Rating | 24VDC, 10A resistive |
Made in Australia – Backed by over 40 years of Bolec engine protection expertise.
Protect Your Engine: DCS 974-T Temperature Switch Modules
Don’t let unexpected engine overheating damage your investment. The DCS 974-T Temperature Switch Modules offer a simple and affordable solution to monitor critical engine surface temperatures.
Key Features & Benefits
- Easy Installation: Includes a simple-to-fit temperature sensing probe that attaches under a bolt head or nut on engine surfaces.
- Robust and Reliable: Housed in durable ABS plastic with an IP65 rating, resistant to dust and water.
- Clear Indicators: LED indicators show Supply ON and Relay status for instant system visibility.
- Easy Adjustment: Front-mounted trim pot and mounting holes for quick setup and calibration.
Invest in engine protection today. Contact us for pricing and availability.
