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Art-n-Marge · 05-18-2010, 08:29 AM

Edited: Added the decibel calculator information.

Regarding the decibels, two items with the same decibels are not completely additive. It will generally be just a little higher. Decibels are logarithmic. Like the earthquake Richter scale, the higher the number the higher the order of magnitude in noise volume. A Honda decibel rating is about the sound of someone talking. With two Hondas running it will sound like two persons talking and assuming no one raises their "voice" you won't notice it unless you are directly next to it and try to speak. Two different generators means the higher db level generator will "cancel" out the lower db level generator. Funny how that works. Here's an decibel calculator, just put all the dbs for two or more devices and it will calculate the dbs for ALL of them:

http://www.sengpielaudio.com/calculator-spl.htm

Put the genny back by the RV connector away from the front door where most company associates and you should be okay (can't say about if the back of your RV is in someone else's front door, but hopefully they are rooting for the other team, eh?)

There are two ratings to worry about for amperage ratings - startup and continuous (running amps). The startup rating is when a device like an A/C uses its 13 amp value. After that, the runtime amperage kicks in, usually much lower in value. The startup value is what could cause a single genny to trip with the A/C starting up, however two gennys should be okay for when this amperage draw occurs. Hondas have a very nice feature call "ECOmode", but this should be turned off when RVing so the generators are running at their best and not as prone to startup amperage problems.

I hope this helps for determining what you need. I have not tried using the MW while the A/C was running since there are so many other ways to cook when RVing. If I had the triple parallel I wouldn't worry about it (assuming it works).

Last thing about using many types of generators, if you have voltage/suppressor/power checking devices in your rig, you might have to modify the power cord to provide "bonding". This should be done anyway but with power monitoring devices this may cause a problem getting power to the rig. Bonding refers to connecting the neutral to ground to prevent electrical shock. When you connect to other power sources that power source provides it (for example a CG power post, or your stickhouse). This is not always provided when connecting to generators. If you have a generator professional installed, this is usually taken care of. Just something else to think about for the best in safety! This is on my things to do - I will make a separate power cord with the bonding wire for use with the gennys. DO NOT use this this power cord with other power sources because DOUBLE bonding is a no-no!

You'll find this supports all the prior posts but with more explanations on how things work. Over the past year I didn't realize how off I was with what I was doing and feel much better with what I've been taught. For example, I gotta get me one of those "clamps" for when I'm not using the generators (that has a ampmeter)

Have fun with this.

05-18-2010, 08:29 AM	#5
Art-n-Marge Montana Master Join Date: Apr 2009 Location: Murrieta Posts: 5,816 M.O.C. #9257	Edited: Added the decibel calculator information. Regarding the decibels, two items with the same decibels are not completely additive. It will generally be just a little higher. Decibels are logarithmic. Like the earthquake Richter scale, the higher the number the higher the order of magnitude in noise volume. A Honda decibel rating is about the sound of someone talking. With two Hondas running it will sound like two persons talking and assuming no one raises their "voice" you won't notice it unless you are directly next to it and try to speak. Two different generators means the higher db level generator will "cancel" out the lower db level generator. Funny how that works. Here's an decibel calculator, just put all the dbs for two or more devices and it will calculate the dbs for ALL of them: http://www.sengpielaudio.com/calculator-spl.htm Put the genny back by the RV connector away from the front door where most company associates and you should be okay (can't say about if the back of your RV is in someone else's front door, but hopefully they are rooting for the other team, eh?) There are two ratings to worry about for amperage ratings - startup and continuous (running amps). The startup rating is when a device like an A/C uses its 13 amp value. After that, the runtime amperage kicks in, usually much lower in value. The startup value is what could cause a single genny to trip with the A/C starting up, however two gennys should be okay for when this amperage draw occurs. Hondas have a very nice feature call "ECOmode", but this should be turned off when RVing so the generators are running at their best and not as prone to startup amperage problems. I hope this helps for determining what you need. I have not tried using the MW while the A/C was running since there are so many other ways to cook when RVing. If I had the triple parallel I wouldn't worry about it (assuming it works). Last thing about using many types of generators, if you have voltage/suppressor/power checking devices in your rig, you might have to modify the power cord to provide "bonding". This should be done anyway but with power monitoring devices this may cause a problem getting power to the rig. Bonding refers to connecting the neutral to ground to prevent electrical shock. When you connect to other power sources that power source provides it (for example a CG power post, or your stickhouse). This is not always provided when connecting to generators. If you have a generator professional installed, this is usually taken care of. Just something else to think about for the best in safety! This is on my things to do - I will make a separate power cord with the bonding wire for use with the gennys. DO NOT use this this power cord with other power sources because DOUBLE bonding is a no-no! You'll find this supports all the prior posts but with more explanations on how things work. Over the past year I didn't realize how off I was with what I was doing and feel much better with what I've been taught. For example, I gotta get me one of those "clamps" for when I'm not using the generators (that has a ampmeter) Have fun with this.