Fan for Generator Sound Shield

[Shrew]

I had a soft sided sound shield fabricated for my Kohler 8
Kw generator. The sound shield has a large fan installed. I'm trying to figure out where to connect the power for the fan.

I was thinking about tying it to the Pos./Grnd to the fuel pump. My thought is the generator starts and closes that circuit, actuating the fuel pump and fan together.

Is there a better idea? Does the Kohler have a place to connect as fan on it??

 

[Turtle Blues]

Controller, fuel pump and shutoff solenoid are all on the same fuse, usually 20A. Not sure what the total draw is, maybe sufficient capacity for the additional load. There are no auxiliary terminals so your installation sounds the most reasonable.

 

[O C Diver]

I might consider a 120 VAC relay on the generator output which would connect the fan to the generator battery. Obviously fuse both the power to the relay and the fan.

Ted

 

[Mischief Managed]

Why does it need a fan? I have never heard of a sound shield needing a fan. Just curious.

 

[Comodave]

Why does it need a fan? I have never heard of a sound shield needing a fan. Just curious.

This is an aftermarket sound shield so it may not have enough ventilation built in. Fan would be a good idea in my opinion. I would go with a 120 volt fan on the genset output as suggested above.

 

[Shrew]

Why does it need a fan? I have never heard of a sound shield needing a fan. Just curious.

I didn't build it. That is the way is came from the company that made it. I assume to promote airflow and cooling.

 

[Shrew]

I neighbor on the dock has the same sound shield. I took a look at his. His fan is wired to the control box, with the ground tied to a common ground, and the lead connected to the backside of the DC breaker.

I don't have the overhead space to do this, even if I completely removed the sound shield and part of the frame. That's why the oem sound shield wasn't installed and why I needed a soft-sided shield.

On my main panel, there is a section for the generator. There is the remote genny start/stop and a blank labelled 'Blower'. I've decided to install a 10a breaker in the blank and I ran 14-2 (tinned marine) wire from the breaker down to the fan.

This would require that we turn the fan on when we start the genny and turn the fan off when we stop it. The two switches are beside each other so, hopefully, this won't be too cumbersome.

I wondering whether this should be wired AC or DC?

 

[Comodave]

I think it would be a PITA to have to turn it on and off manually. I would try to have it on the AC side of the genset and so when the genset starts to put out power the fan would come on and stop when the genset stops. That way you don’t forget to turn it on. Forgetting to turn it off isn’t as big a deal, just waste some battery power.

 

[rgano]

My 3.5 KW NextGen comes with a hard-sided enclosure with a 4-inch hole at the electric end where one attaches a dryer hose leading to a fan which has another short section of hose to the exhaust vent on the side of the hull. This fan cools the generator windings and was originally 12 VDC with no fuse which in turned burned up a lot of the wiring harness when the crummy quality Jabsco blower seized up. The new fan is a brushless AC unit with the power connected to the generator's output so it's operation is automatic. HOWEVER, I was concerned about this expensive and hard-to-access fan being damaged by the hash coming off of the generator while coming up to speed so I installed a delay relay and set it for 30 seconds. Now genny is started, and the fan kicks in after thirty seconds regardless of what position the output breaker on the panel is set to because the delay relay is directly connected to the output before the circuit breaker.

 

[Shrew]

Well, I should have simply looked. After removing the panel and inspecting the fan I as able to determine that it is a 110v/120v | 50hz/60hz fan. I tested it and it seems to blow in the direction regardless of whether you revers the polarity on the leads to the fan. Oddly, this fan seem to blow OUT, however there is a large vent on each end of the sound shield, so cool air should be able to be sucked in on the other side.

I decided to run a decent gauge jumper from the AC power into the panel on the generator side of the breaker to the 10amp breaker I installed in the panel in the generator blower slot. I then ran the fan ground to the ground bus on the panel and the fan power to the blower breaker.

This should allow me to simply keep the breaker on on the blower and the blower will start automatically when the generator starts, regardless of whether I turn the genny breakers on to the panel. It will also allow me to shut off the fan for service.