WELCOME TO RIVER DAVES PLACE

Generator Load Bank questions

RiverDave

In it to win it
Joined
Sep 13, 2007
Messages
126,196
Reaction score
164,413
So this sign truck thing continues.. LOL. The generator is effectively sitting at zero % power usage even with the sign and two AC's running and equipment (processors and laptop).

Because it will start to "wet stack". I am looking for a small load bank that I can hopefully put into the electronics cabinet or one of the cabinets below.

I'm not educated on this stuff but the one that I have found so far with my limited searching is the Simplex Swift-E.

Is there something small I can use to just get this generator to the point where it won't wet stack?

Here's what I found and I'm looking for something even smaller if I can get it?
 

DaveH

Well-Known Member
Joined
Sep 9, 2008
Messages
2,772
Reaction score
3,981
Gen-Tech here in Vegas has various size load banks for testing. Not that you want to drive all this way, but if it comes to it here is an option for you.

also, why such a big generator?
 

The Chicken

off-grid solar installer
Joined
Jan 5, 2016
Messages
157
Reaction score
1,375
What are the actual loads in watts?
What size is the generator?
If the loads aren't crazy, maybe you could put some batteries and an inverter onboard, and have the inverter call for the generator only when the batteries are low, and load the genset more but for shorter times, saving fuel and genset wear and tear?
 

hallett21

Well-Known Member
Joined
Nov 9, 2010
Messages
18,308
Reaction score
23,459
Gen-Tech here in Vegas has various size load banks for testing. Not that you want to drive all this way, but if it comes to it here is an option for you.

also, why such a big generator?
I think he planned on making it a support vehicle for events as well.
 

Waterjunky

RDP Inmate #94
Joined
Sep 24, 2007
Messages
4,913
Reaction score
4,255
well then seems like a small genset to support the realistic load of the truck, wired to a x-fer switch, then run the big daddy when needed. very uneconomical the way its setup. like using a jackhammer to crack an egg.
This.......
 

Mandelon

Coffee makes me poop.
Joined
Sep 24, 2007
Messages
14,588
Reaction score
20,186
Wet stacking is a condition in diesel engines in which unburned fuel passes on into the exhaust system.[1] The word "stacking" comes from the term "stack" for exhaust pipe or chimney stack. The oily exhaust pipe is therefore a "wet stack".

This condition can have several causes. The most common cause is idling the engine for long intervals, which does not generate enough heat in the cylinder for a complete burn. "Idling" may be running at full rated operating speed, but with very little load applied. Another is excessive fueling. That may be caused by weak or leaky injectors, fuel settings turned up too high or over fueling for the given rpms. Cold weather running or other causes that prevent the engine from reaching proper operating temperature can cause a buildup of fuel due to incomplete burn that can result in 'wet stacking'.[2][3] In diesel generators, it is usually because the diesel engine is running at only a small percentage of its rated output. For efficient combustion, a diesel engine should not be run under at least 60 percent of its rated power output.[4]

Wet stacking is detectable by the presence of a black ooze around the exhaust manifold, piping and turbocharger, if fitted. It can be mistaken for lubricating oil in some cases, but it consists of the "heavy ends" of the diesel fuel which do not burn when combustion temperature is too low. The heavier, more oily components of diesel fuel contain more stored energy than a comparable quantity of gasoline, but diesel requires an adequate loading of the engine in order to keep combustion temperature high enough to make use of it. Often, one can hear a slight miss in the engine due to fuel buildup. When the engine is first placed under a load after long periods of idling and wet stacking, it may blow some black exhaust out as it burns that excess fuel off. Continuous black exhaust from the stack when under a constant load is also an indication that some of the fuel is not being burned.[5] Additionally, wet stacking can result in a build up of diesel fuel in the engine which does not combust due to the low temperature in the engine. This results in a reduced fuel economy. This fuel leaks through the cylinders and dilutes the engine oil. If not frequently changed, this diluted oil can lead to increased wear on the cylinder and premature engine failure.[6]
 

Mandelon

Coffee makes me poop.
Joined
Sep 24, 2007
Messages
14,588
Reaction score
20,186
Can you upgrade the alternator to put out more juice....enough to power the screens n bits while the engine is on? Seems like your generator is overkill for a portion of your needs.
 

bilz

Newly Retired!😁
Joined
Mar 15, 2011
Messages
2,668
Reaction score
4,077
Wet stacking is a condition in diesel engines in which unburned fuel passes on into the exhaust system.[1] The word "stacking" comes from the term "stack" for exhaust pipe or chimney stack. The oily exhaust pipe is therefore a "wet stack".

This condition can have several causes. The most common cause is idling the engine for long intervals, which does not generate enough heat in the cylinder for a complete burn. "Idling" may be running at full rated operating speed, but with very little load applied. Another is excessive fueling. That may be caused by weak or leaky injectors, fuel settings turned up too high or over fueling for the given rpms. Cold weather running or other causes that prevent the engine from reaching proper operating temperature can cause a buildup of fuel due to incomplete burn that can result in 'wet stacking'.[2][3] In diesel generators, it is usually because the diesel engine is running at only a small percentage of its rated output. For efficient combustion, a diesel engine should not be run under at least 60 percent of its rated power output.[4]

Wet stacking is detectable by the presence of a black ooze around the exhaust manifold, piping and turbocharger, if fitted. It can be mistaken for lubricating oil in some cases, but it consists of the "heavy ends" of the diesel fuel which do not burn when combustion temperature is too low. The heavier, more oily components of diesel fuel contain more stored energy than a comparable quantity of gasoline, but diesel requires an adequate loading of the engine in order to keep combustion temperature high enough to make use of it. Often, one can hear a slight miss in the engine due to fuel buildup. When the engine is first placed under a load after long periods of idling and wet stacking, it may blow some black exhaust out as it burns that excess fuel off. Continuous black exhaust from the stack when under a constant load is also an indication that some of the fuel is not being burned.[5] Additionally, wet stacking can result in a build up of diesel fuel in the engine which does not combust due to the low temperature in the engine. This results in a reduced fuel economy. This fuel leaks through the cylinders and dilutes the engine oil. If not frequently changed, this diluted oil can lead to increased wear on the cylinder and premature engine failure.[6]
I was just going to look that up, thanks!
 

lbhsbz

Putting on the brakes
Joined
Jan 11, 2010
Messages
13,016
Reaction score
33,481
So this sign truck thing continues.. LOL. The generator is effectively sitting at zero % power usage even with the sign and two AC's running and equipment (processors and laptop).

Because it will start to "wet stack". I am looking for a small load bank that I can hopefully put into the electronics cabinet or one of the cabinets below.

I'm not educated on this stuff but the one that I have found so far with my limited searching is the Simplex Swift-E.

Is there something small I can use to just get this generator to the point where it won't wet stack?

Here's what I found and I'm looking for something even smaller if I can get it?
That's stupid. Get a smaller genset more suited to the loads you're using it for. Adding a load bank is simply a waste of fuel and wear and tear on equipment.
 

Sharky

Well-Known Member
Joined
Jan 11, 2023
Messages
1,655
Reaction score
6,100
Watch e-bay for an old, Onan 300-608 load bank. Or, a 420-385. They pop up from time to time.

They look like this.

Unknown.jpg
 

Joe mama

Well-Known Member
Joined
Oct 22, 2010
Messages
3,869
Reaction score
3,738
This is one of those cases where bigger isn’t better.
Then again it’s better to be looking at it than looking for it.
 

Your ad here

Well-Known Member
Joined
Oct 16, 2014
Messages
5,011
Reaction score
8,398
Who diagnosed the "problem"? It doesn't make sense to me. I suspect there is a circuit board or setting problem. Does produce any electrical power?
 

hallett21

Well-Known Member
Joined
Nov 9, 2010
Messages
18,308
Reaction score
23,459
Trying to think of a justifiable load you can add to run with everything.

My guess is this is all hardwired and Dave doesn’t want to re wire stuff and deal with transfer switches etc.
 
Last edited:

hallett21

Well-Known Member
Joined
Nov 9, 2010
Messages
18,308
Reaction score
23,459
Who diagnosed the "problem"? It doesn't make sense to me. I suspect there is a circuit board or setting problem. Does produce any electrical power?
It’s generating power but his load is too small. I’m sure he’s under 10% load.
 
  • Like
Reactions: Maw

Your ad here

Well-Known Member
Joined
Oct 16, 2014
Messages
5,011
Reaction score
8,398
put in boating terms, it would be like have a turbo 1350 running at idle all day, then adding drag chutes in the water so as to load the engine more but not go any faster,
Not really. Generators have to run at 1800 rpm. Some do have an idle down feature when no load is applied. At 1800 rpm and no load it is creating enough heat to not have immediate problems. When you add a load it will cause the engine to work harder to maintain 1800 rpm and it will create enough heat to burn off whatever it needs to.
 

Your ad here

Well-Known Member
Joined
Oct 16, 2014
Messages
5,011
Reaction score
8,398
It won’t rev enough so it’s building up shit in the exhaust. Or could potentially.
Is it making power and he's worried about wet stacking? The 0% usage in his first post is confusing. Sound like it's not making power because it doesn't sense a load.
 

hallett21

Well-Known Member
Joined
Nov 9, 2010
Messages
18,308
Reaction score
23,459
Is it making power and he's worried about wet stacking? The 0% usage in his first post is confusing. Sound like it's not making power because it doesn't sense a load.

“Effectively zero”
 

DaveH

Well-Known Member
Joined
Sep 9, 2008
Messages
2,772
Reaction score
3,981
Not really. Generators have to run at 1800 rpm. Some do have an idle down feature when no load is applied. At 1800 rpm and no load it is creating enough heat to not have immediate problems. When you add a load it will cause the engine to work harder to maintain 1800 rpm and it will create enough heat to burn off whatever it needs to.
he must not be having any issues then.
 

Your ad here

Well-Known Member
Joined
Oct 16, 2014
Messages
5,011
Reaction score
8,398
he must not be having any issues then.
The original post is confusing. I'm now thinking everything works and its producing power but he's worries about wet stacking because the lack of load? FWIW I see diesel generators run year round powering job site trailers and never heard of one having problems with wet stacking. I have one with 10,000 hours and no problems. The exhaust pipe is sooty but not worried about it.
RD could put an RV plug on it and every 100 hours plug his RV in it and run all the stuff in the RV to create a heavy load so it makes some heat. Run the ACs, dryer, all lights, stereo, ect.
 

Sharky

Well-Known Member
Joined
Jan 11, 2023
Messages
1,655
Reaction score
6,100
Not really. Generators have to run at 1800 rpm. .
Unless it's a Generac. We used to call them Gen-a-racket because they ran at 3600 RPM.

Onan & Honda were smart enough to add 2 more poles in the alternator side (AC) and cut engine speed (noise). Onan was even smarter and added a separate set of poles just for DC generation. That is what powered the ignition & control board on an Onan. You only needed a 12V battery to run the starter on an Onan. That is all the 12V battery does. The separate DC generator takes over to power ignition & board.

Naturally, they cost more.
 

WTMFA

Kill Em All
Joined
Dec 30, 2007
Messages
2,845
Reaction score
410
This is what I do for a living. We have about 14 generators that are used to power the set while filming out on location. There is a load bank back at the shop that we use on occasion for testing and "blowing out" the genny when it's had minimal loads for long periods of time. All that being said, I think you're prematurely worrying about this. "If" the genny is used on a regular basis and is almost constantly under very low loads you would be fine using something to generate a heavy load once a year.
We have gennys that have mechanical fuel injection (way less efficient than electronic fuel injection) that have well over 10k hrs on them and at the most we've only ever load banked them once a year, and that would be on a genny that works on a regular basis out in the field under low load conditions.
You've got my number if you want to discuss in further detail 😉
 

rrrr

Well-Known Member
Joined
Dec 19, 2007
Messages
15,858
Reaction score
35,315
Unless it's a Generac. We used to call them Gen-a-racket because they ran at 3600 RPM.

Onan & Honda were smart enough to add 2 more poles in the alternator side (AC) and cut engine speed (noise). Onan was even smarter and added a separate set of poles just for DC generation. That is what powered the ignition & control board on an Onan. You only needed a 12V battery to run the starter on an Onan. That is all the 12V battery does. The separate DC generator takes over to power ignition & board.

Naturally, they cost more.

Good info. Generator (they're actually alternators) frequency is dependent on the number of rotor poles and stator configuration. The magnetic fields produced by the poles and the RPM determine the frequency of the output. Voltage is produced by those magnetic fields, regulated by varying a smaller voltage on the exciter assembly located on the end of the rotor.

I copied this because it's easier than texting it:

To produce 60 Hz power, engine driven generators will operate at 1800 rpm using a 4-pole generator. Lightweight, portable or residential generators may operate at 3600 rpm with a 2-pole generator. Larger generator sets may run at 1200 rpm (6pole) or 900 rpm (8-pole) or 720 rpm (10pole). (50 Hz is similar but 3,000 rpm for 2-pole, 1500 rpm for 4-pole, 1000 rpm for 6-pole etc.)

I worked in a few older (like 1950-1960s) facilities that had 900 RPM gensets. They were huge compared to their power output. Modern engine and alternator technology has greatly improved that.
 
Last edited:

Blackmagic94

Well-Known Member
Joined
Apr 4, 2017
Messages
5,384
Reaction score
7,393
well then seems like a small genset to support the realistic load of the truck, wired to a x-fer switch, then run the big daddy when needed. very uneconomical the way its setup. like using a jackhammer to crack an egg.
He is using .4-.5 gph. Not really agreeing with the uneconomical way lol
 

Blackmagic94

Well-Known Member
Joined
Apr 4, 2017
Messages
5,384
Reaction score
7,393
Who diagnosed the "problem"? It doesn't make sense to me. I suspect there is a circuit board or setting problem. Does produce any electrical power?
It does. He shows a max of 27% of 10,000 watts then the gauge goes to zero on load use. I believe the load gauge is wrong as it’s impossible to have zero load while two ac units and the other accessories are running. 2700 watts sounds very realistic to me but is still below the 7500-8000 that is recommended for long term use to avoid wet stacking. Hence my suggestion on a load board if he doesn’t want to add more power demand by other means.
 

Blackmagic94

Well-Known Member
Joined
Apr 4, 2017
Messages
5,384
Reaction score
7,393
Trying to think of a justifiable load you can add to run with everything.

My guess is this is all hardwired and Dave doesn’t want to re wire stuff and deal with transfer switches etc.
My suggestion was a 220 volt garage heater to blow through 5000 extra watts. Cheapest fix for 189 bucks. But your gonna be blowing hot ass air straight up the whole time

Maybe a third ac unit that was bigger to blow cold air off to the side where people stand at events. Get a 24,000 btu unit so it draws some power
 

rrrr

Well-Known Member
Joined
Dec 19, 2007
Messages
15,858
Reaction score
35,315
Trying to think of a justifiable load you can add to run with everything.

My guess is this is all hardwired and Dave doesn’t want to re wire stuff and deal with transfer switches etc.

My suggestion was a 220 volt garage heater to blow through 5000 extra watts. Cheapest fix for 189 bucks. But your gonna be blowing hot ass air straight up the whole time

Maybe a third ac unit that was bigger to blow cold air off to the side where people stand at events. Get a 24,000 btu unit so it draws some power

I hadn't thought about how it's power distribution is setup. I guess it's impractical to temporarily connect a significant load to it.
 

n2otoofast4u

Well-Known Member
Joined
Apr 7, 2015
Messages
5,736
Reaction score
11,554
Ray Charles saw this coming. You can power a city with the gen, but a 9v from your smoke detector will power it. Add a battery bank with an auto charge crossover, or go to Harbor Freight and buy a wannabe Honda that will work just fine.
 

HTTP404

New But Seasoned Inmate #2002
Joined
Jun 20, 2008
Messages
3,806
Reaction score
7,292
Throw some of these on there and just charge them with the generator as needed.
 
Top