DEIF DU-2/MKIII – Compact Control/Monitoring Module for Genset and Switchboard Applications

The DEIF DU-2/MKIII is a robust, panel-mounted control and monitoring unit widely used on generator sets and marine/industrial switchboards. From my experience, this series is typically chosen when you need dependable voltage/frequency supervision with adjustable setpoints and clean relay outputs for alarms, trips, or start/stop logic. It seems to be a favorite in retrofit projects because it slots into existing panels without forcing a redesign, and it’s straightforward to set up on site.

Company’s Order Placement Process and Guarantees

• Warranty: 365 days
• Lead time: 1 week if in stock; no more than one month at the latest
• Payment: 50% advance payment, full payment prior to delivery
• Express delivery: FedEx, UPS, DHL

Key Features

• Voltage/Frequency Supervision – Designed to monitor AC parameters and trigger relays when limits are exceeded; adjustable setpoints simplify commissioning.
• Reliable Relay Outputs – Dry contact outputs typically used for trips, alarms, or breaker control, keeping wiring simple for OEMs and service teams.
• Intuitive Setup – Front adjustments and clear status indication make on-site tuning quick; you might notice it reduces start-up time on retrofits.
• Rugged, Panel-Mounted Build – Suited to harsh switchboard environments where vibration and electrical noise are common.
• Drop-in Replacement Potential – In many cases, the DU-series form factor and terminals align well with legacy installations.
• Accessory-Friendly – Works with standard CT/VT sensing and 24 V DC control supplies found in most genset panels.

Technical Specifications

Application Fields

You’ll typically see the DU-2/MKIII in:

• Marine switchboards (auxiliary and emergency gensets) where compact supervisory control is required
• Industrial generator sets in factories, data rooms, and utilities
• Power house panels for CHP, standby power, and load management
• Retrofits of legacy protection/monitoring relays in OEM enclosures

“We replaced a discontinued unit with a DU-series controller and kept the original wiring—saved us a full panel redesign.” — Service contractor, ship repair (shared with permission)

Advantages & Value

• Reliability – DEIF’s marine-grade pedigree shows in stable operation and clean switching behavior.
• Compatibility – Works with standard CT/VT sensing schemes and 24 V DC control supplies commonly found in genset cabinets.
• Lifecycle Savings – Drop-in replacement potential and quick commissioning usually cut engineering hours.
• Technical Support – We verify the exact variant by photo/serial before shipment to match your site wiring and setpoints.

Installation & Maintenance

• Cabinet environment – Install in a clean, dry switchboard with adequate ventilation; follow IP rating requirements for marine or industrial areas.
• Wiring practices – Use segregated routing for AC sensing and DC control; crimp ferrules; ensure protective earth bonding to reduce noise.
• Setpoint verification – After energizing, confirm over/under limits and relay logic by simulation tests before handing over.
• Routine maintenance – Annual visual inspection, terminal re-torque, dust cleaning, and functional tests; firmware updates are typically not required on this series.
• Safety precautions – De-energize circuits, lockout/tagout, and verify absence of voltage on AC sensing lines prior to service.

Quality & Certifications

• CE conformity and RoHS compliance are standard for DEIF industrial control products.
• Marine class approvals (e.g., DNV-GL, ABS, BV) are commonly available depending on the DU-2/MKIII revision; we can confirm against your serial.
• Manufacturer’s warranty support honored; our commercial warranty is 365 days.

Suggested Supporting Components

• 24 V DC industrial power supply sized for control load with surge headroom
• Appropriate CT/VT sensors for the monitored circuit (match burden and ratios)
• Panel accessories: DIN rail terminals, ferrules, and marker labels for clean wiring

If you share a quick photo of the existing DU-2/MKIII or its rating label, we’ll match the exact variant and confirm I/O behavior and supply voltage before you order. That small step typically prevents commissioning surprises.