Coelmo DM600
9 mins read

We had wrote some time ago about innovative installation of Coelmo DM600. The generating set has been installed in the dinette below the table, astern of the mast.

Coelmo DM600 generetor installation
Umberto Manfelotto di Coelmo and Claudio Bonino Direttore di Alfa Ship-yard with the unusual installation

The first result of the test, that is very interesting, is regarding the beaivour of the system realized, while sailing and at anchorage. In this way, the weights have been placed amidship, below sea water line. As consequence we heave experienced an improvement of boat performances having a better stability at anchorage and, during navigation, both while sailing or during engine propulsion, providing a stronger stability conditions, at the end we have experienced reduced rolling and pitching. Just to give you an idea, the feeling is thame as to have two more people on the side.

For what above mentioned, after sailing for a while, under all sailing conditions, we have started the generator for the first time.

To start the generator we have connected the 220V ac power line to the generator by switching the three way diverter from “shore connection” to “generator” passing trough the “zero” position. Next to the diverter, it has been installed Coelmo control panel EOS, the interface communicating with the generator.

Let’s switch on Eos Controller and then let’s start the generating set by pressing START button.

The display switches on providing an acusting signal informing us that the initial checkup has started, this is a feature of innovating EOS control panel. The masseage “Generator OK” appears on the display and we can proceed to start the generator by the START button.

On the display it appears that glow plugs are on along with preheating operation, 10 seconds countdown starts and, once completed, without any other action form our side, Coelmo DM600 display reports “starting” indication and the generator starts running without any hesitation.

coelmo dm600 generator display eos coelmo dm600 generator display eoscoelmo dm600 display eos

The first impression is the noise, or better its absence. We were expecting the usual noise, furthermore the generator has been installed in the dinette, as additional impact. On the contrary, the sound-proof canopy of the generator reduces noise pressure with the maximum value of 44/45 db. As matter of fact we can talk each other without increasing voice volume, and this at about one meter distance from the generator.

Most probably the installation solution itself contributes to the nois reduction, the support of the table of the dinette, being wooden made, represents a furhter barrier to the noise. If the generator should have been installed in a techncial space, as usual in a boat of last generation, most probably, we would not hear noise at all.

coelmo dm600 display eos

Additional sound measurments have been performed in the forward cabin, at about 4 metres distance and, with the door closed, sound pressure measured is about 32/34 db, as matter of fact a background noise only. We are now upstairs on the deck and the only audible noise, is the cooling water exhaust splashing into the sea.

Surprised by the high soudproof insulation reached by the generator, let’s go to have a look of the electrical performances.

No electrical load has been feed yet, the display does not report any load, while the main switchboard indicates that the 220V ac has been connected, an unmistakable sign of high quality electric power generation.

The innovative power management system developed by COELMO safely allows to automatically close the main circuit breaker and supply 220 V ac electrical power only after checking that electrical and mechanical parameters are within establishe range, this avoiding frequency and voltage fluctuations that could damage the on-board equipments.

While the battery charger is already charging on board batteries, we progressively feed other loads to check how the DM600 generator reacts.

We have been trying to simulate real uses on board, feeding some loads in sequence, such as: charger for portable VHF, charger for torqeedo 1003 and finally a 1.800 W hair-dryer, used first with cold air and then with hot air at maximum power. The generator display has showed a load of about 2.2 kW, reporting stable values of frequency and voltage.

coelmo dm600 display noise testWhile applying a progressive increase of the load feeding, the generator has been running smootly without showing any fatigue sign.

Another thing to point out is the total absence of vibrations during functioning; this performance compared with that of other generators, highlights a tangible difference. In fact Coelmo anti-vibration mountings have a great vibrations absorbing effect, reducing vibtations at minimum levels.

We have been leaving the generator running with these loads for about one hour while completing other small jobs on board, and we are close to forget about it.

Having 220V ac available on board makes a very big difference instead of having an inveter. I don’t love inverters, they absorb to much 12V dc current heating connection cables. Furthermore the 12Vdc-220Vac transformation process, produces a very big amount of energy dissipation, overloading on board batteries.

This part of the test is completed, it’s time to turn off our generator, the DM600 is then stopped by the STOP button on the control panel. The message “Stop in progress” appears on the display, alternating with indication “ventilation”. The generator management system opens the main circuit breaker and disconnects the 220 V ac supply to the main switchboard, ensuring the correct electrical voltage and frequency parameters by protecting on board electrical equipment, in this phase too. The generator starts the cooling process and after a few minutes the DM600 turns off without causing any shock or vibration.



Summarizing we are in presence of a great product, total absence of vibration, excellent soundproofing and optimum current output make it a great travel companion.

As mentioned above, to utilize 220V ac users, it is much safer to use a generator than an inverter and, the solution we found, makes this installation possible on any kind of boat, sail-boat or power-boat, able to accommodate the small size of Coelmo DM600.

With 6 kW electrical power on board we can really afford all comforts from an hairdryer for ladies, to the air conditioning. For example, we are seriously thinking about an electrical coffee machine. In conclusion, such kind of generator makes you feeling at home, even if you are at the ancorage in remote bay, without thoughts, safely and, above all, in silence …


coelmo dm 600 generator installation
Before installation. Note the location where the generator is anchored.
coelmo dm 600 generator installation
The dinette when the installation is completed.

Our test has not been dompleted yet. Coelmo DM600 generator will be used constantly during a cruise of several weeks. We will carry out routine maintenance after the first 20 running-hours independently and then we will verify other two very important features, reliability and easy maintenance.


Coelmo DM600 – Technical Data

Model: Coelmo DM600
Power: 6 Kw
Phase: Single-phase
Power factor: 1
Voltage: 230 V
Frequency: 50 Hz
Starting: Eletric [kVA]
Fuel Consumption: 1,6 l/h 50% load – 2.70 l/h max
Noise level: 54 dB(A) 7 meters distance
Cooling-off with heat exchanger
Cylinder capacity 479
Cylinders 2
Revolution per minute 3000
Length 650 mm
Wide 480 mm
Height 530 mm
Weight 128 Kg



1 Comment

  1. I am considering the DM600 and was hopeful you could provide some followup since owning and using it. Thank you

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