The Datakom DKG-105 is a compact automatic mains failure (AMF) controller for generator sets—the small digital brain that watches the utility supply, starts the engine when the grid drops, transfers the load, and shuts everything down safely on a fault. Made by Datakom Electronics of Turkey, it belongs to the entry level of genset control: it fits a standard 72×72 mm panel cutout and is aimed at basic single-set standby installations rather than complex paralleling systems.
This guide is for panel builders, generator technicians, and buyers deciding whether the DKG-105 covers their auto-start needs. It explains what the unit does, its verified specifications, how it wires into a genset, and where its deliberately basic feature set is a strength or a limitation. It is based on Datakom’s published documentation and public product data, not on hands-on testing.
What the DKG-105 does
In automatic mode the DKG-105 continuously monitors all three phases of the mains voltage. If any phase fails or drifts outside the programmed limits, the unit runs its start sequence, cranks the engine (surviving the voltage dropouts that cranking causes), confirms the generator is producing acceptable voltage and frequency, and then transfers the load from the mains contactor to the generator contactor. When the mains returns and stabilizes, it transfers back and runs the engine through a cooldown before stopping. Throughout, it watches internal protections and external fault inputs and shuts down on any alarm condition.
It is a microprocessor-based digital unit with pushbutton programming—no external programmer or laptop is needed. Timers, voltage limits, and speed alarm thresholds are all digitally adjustable from the front panel, and the relay configuration is programmable so the same controller can drive diesel and gasoline (gas) engines, including energize-to-stop fuel arrangements.
Specifications at a glance
| Parameter | Specification |
|---|---|
| Type | Microprocessor AMF / auto-start genset controller |
| DC supply range | 9–33 VDC (4–33 VDC while cranking) |
| Current consumption | 60 mA typical (auto, mains OK); 200 mA max |
| DC output rating | 10 A DC total |
| AC output rating | 10 A AC total; 10 A RMS max per terminal |
| Mains voltage | Up to 277 VAC (Ph-N), 3 phase |
| Alternator voltage | Up to 277 VAC (Ph-N) |
| Frequency | 50/60 Hz; alternator measurement 0–100 Hz |
| Measurement accuracy | Phase voltage 2% + 1 V; frequency ±0.5 Hz |
| Battery voltage | Works on 12 V and 24 V gensets |
| Operating temperature | −20 °C to +70 °C |
| Storage temperature | −30 °C to +80 °C |
| Dimensions | 78 × 78 × 50 mm (W×H×D) |
| Panel cutout | 68 × 68 mm minimum (72×72 mm standard opening) |
| Weight | Approx. 200 g |
| Case material | Flame-retardant ABS/PC (UL94-V0) |
Measurements, inputs and outputs
The DKG-105 keeps its instrumentation intentionally lean. It displays the three mains phase-to-neutral voltages (L1-N, L2-N, L3-N), the generator L1-N voltage, and generator frequency, along with a digital engine run-hours counter. Voltage accuracy is quoted at 2% + 1 V and frequency at ±0.5 Hz—adequate for the go/no-go decisions an AMF unit makes, even if it is not a precision power analyzer.
On the output side there are five control functions. The FUEL relay drives the fuel solenoid (and can be reprogrammed to activate-to-stop). The START relay drives the starter solenoid. The AUXILIARY relay fires on any alarm and can alternatively be configured as a stop solenoid, preheat output, choke output, or gas-engine fuel solenoid—useful flexibility on a low-cost board. Two further outputs energize the generator contactor and mains contactor directly from the respective phase voltages. Total output rating is 10 A DC and 10 A AC, with 10 A RMS maximum per terminal, so contactor coils must be sized within that budget or driven through interposing relays.
Protection inputs are basic but cover the essentials for a small set: a negative-closing low oil pressure switch input and a negative-closing high engine temperature switch input. The unit also provides delayed overspeed and underspeed alarms with digitally adjustable speed limits and a digitally adjustable delay, plus low/high limit checking on both mains and generator phase voltages.
Modes and compatibility
Four modes cover normal operation. In OFF, the mains contactor is energized whenever AC mains is present. AUTOMATIC is the standard standby mode described above. TEST (also called emergency-backup mode) starts the generator without a real mains failure but holds the load on the mains until an actual failure occurs, so you can exercise the set safely. PROGRAM is where timers and operational limits are set via the front pushbuttons.
Because it runs on both 12 V and 24 V systems, drives diesel or gas engines, and accepts a TN or TT power system at up to 277 VAC phase-to-neutral, the DKG-105 suits a broad range of small gensets. It is designed to work alongside the alternator’s own voltage regulator and a battery maintenance charger rather than replacing them. If you are assembling a complete standby set, our guides to the AVR SX460 automatic voltage regulator and the SmartGen BAC06A battery charger cover the two companion components that keep alternator output steady and the starting battery topped up between runs.
Installation and safety considerations
Physically, installation is straightforward: the unit drops into a 72×72 mm panel opening (68×68 mm minimum cutout) and is held by rear plastic retaining brackets, with a plug-in connection system that makes field replacement quick. The flame-retardant ABS/PC case is rated for a Type 1 enclosure and an operating range of −20 °C to +70 °C. Datakom lists conformity with the EU low-voltage and EMC directives and reference norms EN 61010 (safety) and EN 61326 (EMC), and a CAT II measurement category.
That said, wiring an AMF controller means connecting to mains-voltage contactor circuits and to a genset’s DC starting system, both of which are hazardous. Contactor coil currents must stay inside the 10 A per-terminal limit, protection switch inputs must be the correct negative-closing type, and the changeover logic must be verified before the set is trusted for automatic operation. This is work for a qualified generator or electrical technician, following proper isolation procedures and the manufacturer’s terminal diagram—not a job to improvise. Always commission the transfer sequence with the engine safely able to be stopped.
Pros and cons
- Strengths
- Genuinely low-cost, compact AMF control in a standard 72×72 mm format
- Three-phase mains monitoring with automatic start, transfer, and shutdown
- Front-panel pushbutton programming—no laptop or external tool needed
- Flexible auxiliary output configurable for stop, preheat, choke, or gas fuel
- Runs on 12 V or 24 V systems and supports diesel and gas engines
- Plug-in connector and rear brackets make replacement fast
- Limitations
- Basic instrumentation: no current/power metering, only voltage and frequency
- Minimal built-in protections (oil pressure, temperature, over/underspeed)—no dedicated overcurrent or earth-fault
- No magnetic-pickup speed input listed; speed alarms rely on frequency
- Single generator only—no paralleling or synchronizing
- Modest 10 A output budget may require interposing relays for large contactors
Who it’s for (and who should look elsewhere)
The DKG-105 is aimed squarely at basic single-set standby applications: a shop, small facility, farm, or telecom cabinet that needs the generator to start and take the load automatically when the grid fails, without the cost or complexity of a full-featured controller. For that job it is well matched, and its low price and standard panel size make it easy to specify or retrofit.
Buyers who need current and power metering, event logging, CAN/J1939 engine communication, or remote monitoring should step up within Datakom’s own range—models such as the D-500 or the DKG-307/DKG-507 series add those capabilities—or consider comparable controllers like the DSE (Deep Sea Electronics) 4520 or a SmartGen HGM6120. Anyone planning to parallel multiple sets or synchronize with the mains needs a dedicated paralleling controller, which the DKG-105 is not.
Frequently asked questions
Does the DKG-105 work on both 12 V and 24 V gensets?
Yes. Its DC supply range is 9–33 VDC (dropping to 4–33 VDC during cranking so it survives crank dropouts), which covers both 12 V and 24 V starting systems without any hardware change.
Can it control a gasoline (gas) engine, not just diesel?
Yes. The relay configuration is programmable and the unit explicitly supports gas engines, with provision for energize-to-stop, preheat, and choke outputs. The auxiliary relay can be configured as a gas-engine fuel solenoid, among other roles.
What protections does it include?
It accepts negative-closing low-oil-pressure and high-temperature switch inputs, provides delayed over/underspeed alarms with adjustable limits, and checks low and high voltage limits on both mains and generator phases, shutting down on any alarm condition. It does not include dedicated overcurrent or earth-fault protection.
What size panel opening does it need?
It fits a standard 72×72 mm panel meter opening with a minimum cutout of 68×68 mm. The body measures 78 × 78 × 50 mm and it secures with rear plastic retaining brackets, so retrofitting into an existing 72×72 slot is simple.
Can it parallel two generators or sync to the grid?
No. The DKG-105 is a single-set automatic mains failure controller. Paralleling, load sharing, and mains synchronization require a dedicated synchronizing controller from a higher tier.
Bottom line
The Datakom DKG-105 is a sensible, budget-friendly answer to one specific need: reliable, automatic start-and-transfer control for a single standby generator. On paper it delivers the essentials—three-phase mains monitoring, programmable diesel or gas engine control, the core engine protections, and front-panel setup—in a standard 72×72 mm package that is easy to fit and cheap to replace. Its instrumentation and protection are deliberately minimal, so installations that need metering, communications, or paralleling should look higher up the range. But for a straightforward AMF build where cost and simplicity matter, the DKG-105 covers the basics competently, provided a qualified technician wires and commissions it.