Powerboost Generator Questions

[BLoflin]

Another attempt at explaining...

Your RV is 30A @ 120V = 3.6KWs. When running the RV Air-conditioner and a vacuum (or could have done it by using the microwave) you pulled more than 30Amps (at least initially when the vacuum motor first started, or when the Air Conditioner compressor cycled back on). Motors and compressors always have large (but short duration) surges during startup.

The truck tripped instead of the RV breaker, because breakers are "dumb" they trip due to heat (because of current over rating). So there is some "lee way" and also a timing consideration. Most breakers can tolerate 10% over current rating if for an extremely short time. The PowerBoost seems to have much more intelligence and is actually measuring current draw. So it tripped first.

When you plugged your vacuum in with an extension cord into the other outlets in the truck, you were just lucky and plugged into the outlet wired to the other side of the PB "generator".

RVers fairly quickly learn they can not have the Air Conditioner going full blast while the coffee pot is brewing and someone is using a hair dryer. Same issue you had.

So to come full circle to your question of is PB a 7.2KW geny or two 3.6KW genys? It is a 7.2KW geny when driving a 240V load (with 30A available). For 120V loads there are 2 circuits of 30Amps each.

If your RV is only 30amp (most are, and, of course, we are talking 120V), then when you plug into PB you will get 30A, if you plug into a power pedestal at an RV site you will get 30A. If you have a bigger gas generator (say a 50A which is 6KW at 120V), you couldn't use all 50A with your RV as your main breaker on your RV will eventually trip (at 30A load or slightly more). If you had 2 smaller generators that you coupled together, you still couldn't use all the Amps

For a regular 30A service RV you want to get one of the dogbone connectors (others have put links to Amazon) that will let you plug your 3 pin 30A RV cord into the Round 4 pin (NEMA 14-30) PB plug. So you can get full 30amps. Otherwise, if you use the regular outlets on the PB you are limited to 20A, each.

If you have a bigger RV (that has 2 Air Conditioners) you will have a 4 pin 50 Amp service. This is actually 2 separate 120V 50Amp circuits inside the RV. With 1 Air Conditioner on each circuit and some of the rest of the devices split between the circuits. You can get a dog bone plug that will connect the two 120V circuits in the PB Nema-14 plug and connect it to the RV 4 pin cord. However, of course you will only get 30Amps out of each leg (not the full 50, which you might get at an RV power pedestal). However, I've found, that though the design definition for the 4 pin RV plug is two 120Vs circuits at 50Amps, in reality, they balance around 30Amp of load in the RV on each leg).

Sponsored

 

[BRDVPRA]

Well, that’s true. The adapter is tapping only one of the two circuits on the PB. But that’s all your trailer can use. You and I are using the same set up. The reason the truck trips first is not because of 240V verses 120V, what is happening is that the truck has less tolerance than your trailer. They are rated the same, but the truck trips a little more short of the 3600W mark than your trailer does.

A good analogy is a 30A campground pedestal. Most of them will actually trip at about 23-24A even though it is rated for 30A. That’s why the breaker on the pedestal will ordinarily trip before the breaker on your trailer. Same principal with the truck.

Thanks for the explanation.....back to power management I reckon! We can run it from a 15amp. Just have to actively manage what you are doing. For the record, inside the truck is one leg and outside the truck is the other leg. Now I have not tested the multiple outlets in the bed. Some of those may be split to between the legs too. Thanks again

 

[BRDVPRA]

Another attempt at explaining...

Your RV is 30A @ 120V = 3.6KWs. When running the RV Air-conditioner and a vacuum (or could have done it by using the microwave) you pulled more than 30Amps (at least initially when the vacuum motor first started, or when the Air Conditioner compressor cycled back on). Motors and compressors always have large (but short duration) surges during startup.

The truck tripped instead of the RV breaker, because breakers are "dumb" they trip due to heat (because of current over rating). So there is some "lee way" and also a timing consideration. Most breakers can tolerate 10% over current rating if for an extremely short time. The PowerBoost seems to have much more intelligence and is actually measuring current draw. So it tripped first.

When you plugged your vacuum in with an extension cord into the other outlets in the truck, you were just lucky and plugged into the outlet wired to the other side of the PB "generator".

RVers fairly quickly learn they can not have the Air Conditioner going full blast while the coffee pot is brewing and someone is using a hair dryer. Same issue you had.

So to come full circle to your question of is PB a 7.2KW geny or two 3.6KW genys? It is a 7.2KW geny when driving a 240V load (with 30A available). For 120V loads there are 2 circuits of 30Amps each.

If your RV is only 30amp (most are, and, of course, we are talking 120V), then when you plug into PB you will get 30A, if you plug into a power pedestal at an RV site you will get 30A. If you have a bigger gas generator (say a 50A which is 6KW at 120V), you couldn't use all 50A with your RV as your main breaker on your RV will eventually trip (at 30A load or slightly more). If you had 2 smaller generators that you coupled together, you still couldn't use all the Amps

For a regular 30A service RV you want to get one of the dogbone connectors (others have put links to Amazon) that will let you plug your 3 pin 30A RV cord into the Round 4 pin (NEMA 14-30) PB plug. So you can get full 30amps. Otherwise, if you use the regular outlets on the PB you are limited to 20A, each.

If you have a bigger RV (that has 2 Air Conditioners) you will have a 4 pin 50 Amp service. This is actually 2 separate 120V 50Amp circuits inside the RV. With 1 Air Conditioner on each circuit and some of the rest of the devices split between the circuits. You can get a dog bone plug that will connect the two 120V circuits in the PB Nema-14 plug and connect it to the RV 4 pin cord. However, of course you will only get 30Amps out of each leg (not the full 50, which you might get at an RV power pedestal). However, I've found, that though the design definition for the 4 pin RV plug is two 120Vs circuits at 50Amps, in reality, they balance around 30Amp of load in the RV on each leg).

Thanks for taking the time to clarify this!

 

[BRDVPRA]

If you plugged something into the truck while using just one leg of the 240V plug in the back, you could have started drawing from the other hot leg and not realized it. You would have to repeat the process and bring up the ProPower screen in the truck to see the loads on leg A and B to verify.

Yes I was using the other leg which was my point. Pretty cool from that aspect I guess! Inside the truck is the 20amp leg and outside the truck is the other leg up to 30amp on the twist lock.

 

[snyce1]

Hey All,
I am 30K miles into my PB at this point and I have used the generators for charging drone batteries and other stuff, so I'm pretty familiar with the operation. I have even used it to run a camper A/C at times. My question is this.... While it claims to have 7.2 generator, would it be better to say it has two 3.6 generators that cannot be ran in parallel with each other to achieve the claimed 7.2?

As you all know, those are two totally separate abilities. I say this because I was powering my camper with my truck and I had the A/C running. I then tried to vacuum the camper at the same time. The 3.6 outboard generator tripped. I sure would have thought both generators would push the true 7.2KW/ 30amp through the 30amp twist lock plug, but I don't think that is the case.

I then plugged the vacuum into the truck receptacles and it ran both the A/C and the vacuum like a champ. Now this is a bit silly IMO. Why would anyone want to have to use two separate plugs like this?

Is there a way to get the full 7.2 through the 30 amp plug that i'm missing? Please tell me what i'm missing here, otherwise I may as well just have my suite case honda hooked up....ugh. I can run two of those in parallel.

Glad your generator works . Many do not . The only way to couple the A and B is thru the 220 plug otherwise need seperate lines from A and B bank . On rare occasions when mine has worked i put a 1500 w device in each (heaters ) . I then get up to about 3500 on each without tripping it as long as it is dry . My system unfortunately faults if any moisture around and waiting for engineers to develop an OTA power update to address it as dealer cannot figure it out .

 

[JEB]

Thanks for the explanation.....back to power management I reckon! We can run it from a 15amp. Just have to actively manage what you are doing. For the record, inside the truck is one leg and outside the truck is the other leg. Now I have not tested the multiple outlets in the bed. Some of those may be split to between the legs too. Thanks again

It’s actually a bit more complicated and flexible than that. The adapter you’re using to convert the generator socket into a 30A RV receptacle is wired to tap only one leg of the generator socket. One of the hot pins on the four pronged adapter is actually dead, so it only looks like you have access to one of the two circuits in the bed. On my adapter it’s the B circuit that’s live. But the generator socket actually has two energized legs and with the right adapter—the 50A adapter I reference above, for example—you can access both the A and B circuits simultaneously in the bed using the generator socket. And you can also combine the circuits if you need 240V. In addition, the 20A sockets in the bed give you access to both the A and B circuits simultaneously. One pair accesses the A circuit, one pair accesses the B circuit. Which accesses which is marked on the weather cover.

But you’re right about power management—you need to be very careful to avoid loading up everything on one circuit. I know that when my trailer is hooked up while boondocking, it’s drawing power from the B circuit. So, I put a piece of blue painter’s tape over the weather cover for the 20A sockets that accesses the B circuit to remind me not to use those sockets and to use only the A circuit sockets in the bed if I need more power.

 

[imnuts]

Yes I was using the other leg which was my point. Pretty cool from that aspect I guess! Inside the truck is the 20amp leg and outside the truck is the other leg up to 30amp on the twist lock.

Inside the cab runs on one leg. The 120V bed receptacles are split. One gang is Leg A and the other is Leg B. The 240V uses both hot legs, but as mentioned, you're only using one of them. You can only get 20A from the 120V receptacles, but you can get 30A from each hot leg of the 240V.

 

[Snakebitten]

This is the combination of dogbones I use to run my RV, both my RV and my brothers RV, or if I wanted to just run my brother's RV on 50A.

Most often for short-term power outages, I just run my 30A RV, and depending on which of the 2 orange outlets I choose, that's the bank I'm using on the generator. I can still use the regular 110 20A outlet in the bed of the truck to tap the other bank if I want to blow dry my hair while the AC is on in the RV. Lol

 

[John_C]

It's been mentioned elsewhere, but you'll really see big improvements if you add slow starters to your big draw items.

I use my truck for work, and the generator really sees a lot of use. Sometimes a few hundred watts to charge up power tool batteries, or to run dewatering pumps. Sometimes 4,500-5,500 watts to run electric heaters all day. Works great for that.

But one of my tools (handheld concrete coring drill) use to trip the breakers instantly, every time. Even it if was the only thing plugged in, it would instantly trip. Turns out, the thing pulls like 50 amps of juice at startup for a couple of seconds when I test it on a 20 amp outlet at our shop.

Usually, any appliance with a motor (vacuum cleaner, A/C compressor, refrigerator compressor, air compressors, etc) has a high current draw to get that motor spinning up to speed. The bigger the motor, the bigger the surge. But there is fix!!

For plug in appliances, I highly recommend the Raymond innovations soft starter. It just plugs in, then you plug your high startup device into it. It ramps the supply of power, and completely eliminates the huge startup surge. It's programmable as well, so you can customize how long of a ramp up it uses, and other settings as well. You can also have slow start capacitors installed on your AC condensor to get the same affect without needing to plug it into a stand alone module. Well worth it!

 

[Keith Hoover]

Yes you can, sort of. This will deliver a combined 7200 watts on two 30A, 120V poles. https://www.amazon.com/gp/product/B076ZTZMHM/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

When I plug in my RV to the 30 amp it only draws from the B side and trips if it reaches max output. I thought the 30 amp was supposed to draw from both and and B. I'm finding conflicting videos/info online. So will the adapter provided in the link solve my problem? Thank you

 

[JEB]

When I plug in my RV to the 30 amp it only draws from the B side and trips if it reaches max output. I thought the 30 amp was supposed to draw from both and and B. I'm finding conflicting videos/info online. So will the adapter provided in the link solve my problem? Thank you

No. A typical trailer with 30A service can only use a maximum of 30A at 120V. 30A x 120V = 3600W, which is one leg/circuit of the PB. You can’t combine the circuits and keep it at 120V. As a result, generator socket to 30A RV adapters are deliberately designed to tap only one leg because that’s all the RV can use. The adapter I referenced is for 50A RVs that have two independent circuits and can safely use both of the PB’s legs at the same time. But even these adapters don’t combine the circuits. They’re still independent—they just travel in parallel along the same cable.

EDIT: Think of the PB’s 30A generator socket as no different from the 50A service at an RV park, except that it can provide only 7200W (2X30A) instead of 12000 (2X50A) at 120V. From that perspective, maybe this will help explain why you can only get a maximum of 3600W (1X30A) if your trailer has only a 30A load center providing power to the internal branch circuits. https://koa.com/blog/30-vs-50-amp-rv-service/

 

[Keith Hoover]

No. A typical trailer with 30A service can only use a maximum of 30A at 120V. 30A x 120V = 3600W, which is one leg/circuit of the PB. You can’t combine the circuits and keep it at 120V. As a result, generator socket to 30A RV adapters are deliberately designed to tap only one leg because that’s all the RV can use. The adapter I referenced is for 50A RVs that have two independent circuits and can safely use both of the PB’s legs at the same time. But even these adapters don’t combine the circuits. They’re still independent—they just travel in parallel along the same cable.

EDIT: Think of the PB’s 30A generator socket as no different from the 50A service at an RV park, except that it can provide only 7200W (2X30A) instead of 12000 (2X50A) at 120V. From that perspective, maybe this will help explain why you can only get a maximum of 3600W (1X30A) if your trailer has only a 30A load center providing power to the internal branch circuits. https://koa.com/blog/30-vs-50-amp-rv-service/

Thank you for clearing this up for me. I appreciate it.

 

[Pitago]

Yes you can, sort of. This will deliver a combined 7200 watts on two 30A, 120V poles. https://www.amazon.com/gp/product/B076ZTZMHM/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Guess I'll be purchasing both plugs 50 &30 amps for RV 30 amp and to charge my Mache with 50 amp of course not at the same time

 

[amschind]

You have two 120V 30A AC lines that are 180 degrees out of phase. If you look at an old dryer plug or a welder plug, it has ground and hot leg1 and hot leg2. A newer dryer plug has those three plus a neutral. Either hot run to the neutral is 120V and 30A. If you connect hot leg1 to hot leg2, you have 240V 30A. The new dryers have both 240 and 120V AC, so they have the extra neutral to allow the device to use 120 or 240V from the same plug. So saying that you have two 30A 120V legs is correct, but you double the wattage (without changing the amperage) if you utilize the fact that the sine waves are in opposite phases.

 

[Hullguy]

You have two 120V 30A AC lines that are 180 degrees out of phase. If you look at an old dryer plug or a welder plug, it has ground and hot leg1 and hot leg2. A newer dryer plug has those three plus a neutral. Either hot run to the neutral is 120V and 30A. If you connect hot leg1 to hot leg2, you have 240V 30A. The new dryers have both 240 and 120V AC, so they have the extra neutral to allow the device to use 120 or 240V from the same plug. So saying that you have two 30A 120V legs is correct, but you double the wattage (without changing the amperage) if you utilize the fact that the sine waves are in opposite phases.

They used to bond the old dryers with the neutral, which is why the old dryers were 3 prong plugs. The newer dryers with the 4 prong plugs are because electrical code changed and they require a separate ground to be run for a dryer outlet require the 4 th prong. There can only be one neutral

Sponsored