Time to check out the generator.

[DarkBlack]

Around here summer gas is tweaked to lower the vapor pressure and winter gas has additional oxygenates. That's pretty much the case in any area in the US under air quality regulations.

Winter gasoline has cheap butane added which summer gasoline doesn’t allow. That’s the biggest difference.

 

[RjCorazza]

My guess is that the demand for close to immediate power transfer trumps the best practice of a short warmup for diesels. I suspect in reality your diesel genset would have a shorter life under laboratory conditions... so maybe it would need an overhaul at 6000 hours rather than something slightly higher.
I personally wouldn't worry about it.

I have always wanted a Kubota GL1100, I'm sure you will like it.

 

[JimRB]

Rambling thoughts about that startup load.

The magic might be the hours per year a generator engine might run. A few premature loads on a diesel generator might not be a big deal if it only runs 40 hours a year including quarterly test starts. My 2004 diesel truck has 6500 hours and 200,000 miles. My 1997 JD tractor has 1,300 hours. My 2003 VW Jetta TDI has 700,000 mile on it. Those few data points are just suggesting a diesel engine could last a long time even with a few loads applied quickly. Another not helpful observation. My house is using 350 watts right now. Fridge just kicked on and it is using 560 watts. It spikes up to about 6,000 watts when HVAC and TV is running. Small house of 1,700 sf or 2,700 depending on how you measure and two people. Load might not be that high sometimes when that generator starts.

I work for a doctors office that has 4 ambulatory surgery centers. I have not looked at the generators we have at work. I suspect two run on natural gas. The other might be a diesel. Other center runs on a fair sized APC UPS. The one I think that runs on diesel crapped out this spring after just 15 years. Engine did not die, control parts and the manufacturer said no longer available. Loaner generator sat in parking lot until new generator was installed.

 

[DarkBlack]

A question on the warmup time for Diesel powered generators.

First, the background:

When I last hooked up my PTO generator to test, I decided I was getting too old to deal with the hassle. Taking the existing implement off the tractor and attaching the genny for a power outage that may only last a short period of time, seemed like more effort than it was worth. Losing use of the tractor for other purposes during longer outages, and having to refuel it outdoors during bad weather, was also a negative.

Earlier this month, I sold the PTO genny, which had served me well for many years, and bought a Kubota GL11000 standalone diesel generator. I'm in the process of installing it in the back of one of the barns with an automatic transfer switch. It's been a learning experience so far and not without issues.

The question:

The generator has the OEM automatic transfer option, which starts the engine 20 seconds after the power goes out. 10 seconds later, the transfer relay activates, and generator power is restored to the house.

This is what I don't understand: The manual says to warm the engine for 5 to 20 minutes, depending on temperature, before applying load. Otherwise engine damage could occur. The factory installed transfer switch applies the load just 10 seconds after the engine starts. Why would the engineers design a transfer switch that could damage the engine?

This short delay between outage and switch to generator power is common for propane and gasoline powered systems but does not seem appropriate for diesel. The manuals for all the diesel tractors I've owned say to warm the engine before applying load.

Yet I see many diesel powered systems that ignore the warmup period. People frequently jump in their diesel pickups, start them and drive away. The twin Cummins diesel powered generators in the basement of the building where I used to work, transfer from commercial to generator power in less than 5 seconds. What gives? Is there something magic about diesel engines used to power generators?

Cars and trucks start up to a fast idle speed. Your generator goes racing right to 3,600 rpm’s, right? Those 10 seconds are the same oil pump revolutions and fuel heating as a car or truck fast idle for 30 seconds.
If your initial load isn’t a full load, which it shouldn’t be since big loads like AC compressors have a power restoration delay, then the load should be insignificant to the longevity. If your in a really cold winter condition, you have the option of using a 5w-x weight oil if it brings more peace of mind.

 

[LouNY]

Most all of the automatic transfer generators have a rapid response time, most of the larger and hopefully longer life units have block and or oil heaters to keep the engine internals at a moderately warm temperature. To ease the wear and shock on a cold engine to the sudden start and loading. Years ago some of the larger diesel units had a much longer time delay before being ramped up to speed and the load being applied, I recall a few 100 to 500 KW units that didn't start generating for about 5 minutes after the start command, they actually had 24 volt DC oil prelube pumps for pre and after lubing of the engines, as well as oil and water heaters that kept the fluids up to 60-90 F. And some had automatic oil level maintainers using float valves and 55 gallon drums of oil in gravity feeds. Some were hi speed units of 1800 rpm many at 900 rpm and a few at 1200 rpm.

 

[bdhsfz6]

My guess is that the demand for close to immediate power transfer trumps the best practice of a short warmup for diesels. I suspect in reality your diesel genset would have a shorter life under laboratory conditions... so maybe it would need an overhaul at 6000 hours rather than something slightly higher.
I personally wouldn't worry about it.

I have always wanted a Kubota GL1100, I'm sure you will like it.

I've been looking at them for some time myself. I was able to swing it by selling a few unused implements, including the PTO generator.

I bought from Absolute Generator in Iowa.

Diesel Generators | Absolute Generators: 10 kW-15 kW and 16 kW - 19 kW

Diesel generators require less upkeep and are more efficient than other fuel types. They are typically preferred for their efficiency and low maintenance. Shop our huge selection of diesel generators online now.. 10 kW-15 kW and 16 kW - 19 kW

www.absolutegenerators.com

Not the lowest price but not bad either. I spoke with them on the phone and they answered my questions immediately. They seem to be a knowledgeable, reliable company and offer parts & service for what they sell. Had the unit in less than a week.

I was originally interested in the GL14000 model but they talked me out of it. They said it was too big for my needs. Saved me $3K.

 

[ultrarunner]

Block Heater is the key and in 30 years the heaters last about 7-10 years.

Our smaller Cummins 150kW standby generators must transfer within 10 seconds from power outage to powering load at the hospital.

 

[DarkBlack]

Unfortunately with an emergency generator, you can’t save electricity by running the block heater when you need it, like a vehicle. You need it powered 24/7

 

[DarkBlack]

I’ve worked with big V8 , V10 diesel UPS generators. 0 seconds warmup period. Instant full load the moment the engines got instantly twisted up to 1,800 rpm’s. They had been doing this with almost daily starts for over 20 years with no rebuilds.
Only luxury they got were coolant heaters to keep the engines around 70f.
Goes to show..

 

[ultrarunner]

Yep… cycles on/off 24/7 keeping the coolant at 180 F

When it starts it’s pedal to the metal and transfers in 6-7 seconds…

The freeze plug heaters are short lived compared to the in-line hose heater giving me the longest life…

 

[Rmart30]

Lost electric today for 8 hours. It was a good inspiration for me to test out the generator before winter. Got it all working fine and ran out some old gas it had in it. Last winter, never needed it. Good to know its there and working.

Gave up on generator back ups and got solar back up.
Too much trouble as we get older to keep 30 gallons of gasoline on hand and rotated out couple times a year to keep fresh on hand. I still have a 5000w electric start predator if needed. it will charge my batteries if we dont get much sun. I can run it 6 hours to recharge, rather than running it 24 hours to power the house.
This set up is what I went with basically. I just have 3 of those batteries instead of one as in video.
The benefit is its a back up, but its also not a $2500 whole home generator that does nothing 95% of the year. This one we can use to run our ac during the warmer months. Plus 30% tax credit. Can do one similar to the one in video as low as $1500. Ive got $3500 in my set up. we probably save $50-85 a month on power.

 

[ponytug]

Our utility is sufficiently unreliable that we have the whole catastrophe; solar, batteries, generators.

The nice thing about batteries, even for commercial deployments is that they pick up the load in a fraction of a second, supplies the essential power on while the generators starts and warms up, allowing the generators to get well lubricated up, with warm oil, block, and coolant before transferring the load to the generators. For commercial accounts, the batteries often pay for themselves in a couple of years from the reduction load management/peak demand charges, while also saving wear and tear on the gen sets.

Ten seconds isn't a lot of time for a diesel engine, and certainly not enough to come to equilibrium, but I do understand that for hospitals, people's lives are definitely on the line, and it is what it is.

@ultrarunner are your ORs on UPS systems, or do they go dark when the power drops unexpectedly?

All the best,

Peter

 

[groundcover]

60 KW LP gen set in town. Talked to Cat about disconnecting the block heater at least for the summer. Tech said leave it alone, this unit will use way more power than it ever makes ! We did at least add a thermostat to switch it off when up to temp.

 

[ultrarunner]

Our utility is sufficiently unreliable that we have the whole catastrophe; solar, batteries, generators.

The nice thing about batteries, even for commercial deployments is that they pick up the load in a fraction of a second, supplies the essential power on while the generators starts and warms up, allowing the generators to get well lubricated up, with warm oil, block, and coolant before transferring the load to the generators. For commercial accounts, the batteries often pay for themselves in a couple of years from the reduction load management/peak demand charges, while also saving wear and tear on the gen sets.

Ten seconds isn't a lot of time for a diesel engine, and certainly not enough to come to equilibrium, but I do understand that for hospitals, people's lives are definitely on the line, and it is what it is.

@ultrarunner are your ORs on UPS systems, or do they go dark when the power drops unexpectedly?

All the best,

Peter

Good question...

They never go dark because of the battery powered wall packs and things like medical and surgical equipment are on battery backup to bridge the 10 seconds allowed for backup power to kick in.

That said some lights will go dark for a few seconds but not say a microscope or eye laser...

The corridor light will go dark a few seconds and anything not on backup power will be offline like blanket warmers and similar...

 

[bdhsfz6]

Genset warmups have been discussed, but what about cool down? The manuals in several I've looked at recommend running the engine for 5 - 10 minutes with no load before shutting down. This is the manual page for the Kubota GL11000:

I understand the need for a warmup period, but cool down? In any case, an automatic transfer switch takes neither into consideration.

As posted by several others, it may well be that the relatively low run time of a consumer grade genset is low enough to make these warm up and cool down cycles less important. However, IMO, it's the number of start-stop cycles that counts. The actual run time is irrelevant.

The number of recommended monthly, or quarterly, start-stop maintenance cycles will add up over time.

 

[DarkBlack]

The big UPS generators I was involved with, that had literally zero seconds warmup time, were programmed to run 5 minutes cooldown after the load switched out. They were turbocharged engines though.

 

[grsthegreat]

An automatic transfer switch does take into account warm up and unloaded cool down. But the times arnt very long. Generac uses a temp probe that allows a longer warm up time if ambient temps are very low, but only allows a 1 minute unloaded cool down time.

But one thing, when the home standby is running, and if the enclosure is allowed to remain closed and sealed, the unit pushes a massive amount of air over the engine. This helps keep the engine cool. Running it unloaded places less stress on engine and helps it cool down a bit more before shutting down.

 

[ponytug]

Genset warmups have been discussed, but what about cool down? The manuals in several I've looked at recommend running the engine for 5 - 10 minutes with no load before shutting down. This is the manual page for the Kubota GL11000:

View attachment 1690916

I understand the need for a warmup period, but cool down? In any case, an automatic transfer switch takes neither into consideration.

As posted by several others, it may well be that the relatively low run time of a consumer grade genset is low enough to make these warm up and cool down cycles less important. However, IMO, it's the number of start-stop cycles that counts. The actual run time is irrelevant.

The number of recommended monthly, or quarterly, start-stop maintenance cycles will add up over time.

Many (most?) automatic transfer switches have the ability to have warm up and cool down timers on the load transfer. For some reason, lots of folks skip the warm up in favor of an immediate transfer, but that doesn't make it good for the generator. Same for cool down. Most of the bigger generators that I have worked with have a 5-10 minute cool down ramp. Given the cost of the generator, the cool down periods always seemed to me to be a smart thing to do. I think that older engines were not as highly optimized for cooling, and often developed hot spots that needed to be cooled to reduce warping and cracking, but that's just an opinion.

Personally, if I have been running an engine under heavy loads, I give it a chance to idle down and cool off, but check your owner's manual, as I have seen advice to the contrary, especially in new engines.

All the best,

Peter

 

[bdhsfz6]

An automatic transfer switch does take into account warm up and unloaded cool down. But the times arnt very long. Generac uses a temp probe that allows a longer warm up time if ambient temps are very low, but only allows a 1 minute unloaded cool down time.

But one thing, when the home standby is running, and if the enclosure is allowed to remain closed and sealed, the unit pushes a massive amount of air over the engine. This helps keep the engine cool. Running it unloaded places less stress on engine and helps it cool down a bit more before shutting down.

I think this depends on the switch. My brother's Generac has no warm up or cool down cycle.

 

[grsthegreat]

I think this depends on the switch. My brother's Generac has no warm up or cool down cycle.

. ? . Every generac standby, not portable, ive ever worked on has both. The control is not in the switch, its in the generator controls. Now,if the unit has been changed over to a 2 wire start, than all bets are off.