Diesel fuel life in a standby generator

[weeds]

I am the process of installing an 88KVA generator into one of our plants which will be on standby for when we have a black or brown out.......

the supplier couldn't really tell at what interval should we drain the diesel and replace with fresh diesel

We are not talking about a large volume, it will either be 250L or 410L that will either be dumped or used in our mobile plant (not that I'm real keen using it in the mobile plant). The generator will have a pre-started and tricked into phase failure every two weeks to ensure all is good, it will probably run for 30min burning approx. 6L of diesel

My thoughts is every 12 months, my experience with trucks parked up for a long time is to ensure the tank is full

Interested in your thoughts..."..

[Homestar]

I've been servicing standby gensets for 15 years, and I've seen diesel that has tested up fine after 5 and 10 years. The oldest fuel I've seen test up well was some fuel oil that had been sitting in an underground tank, 5 stories below a high rise in Melbourne that had been there for 30 years. the gensets ran fine on it and could take full load without issue. If you keep the tank full, so no condensation forms in it, it will last for years.

[Blknight.aus]

From memory the book for the gensets that form up part of the field power distrribution system reccomedn that if the fuel isnt going to be used in 6 months that it be drained and replaced. however the onboard tanks are quite small and generally rely on daily refueling or 44 gallon drum feeders.

[weeds]

I've been servicing standby gensets for 15 years, and I've seen diesel that has tested up fine after 5 and 10 years. The oldest fuel I've seen test up well was some fuel oil that had been sitting in an underground tank, 5 stories below a high rise in Melbourne that had been there for 30 years. the gensets ran fine on it and could take full load without issue. If you keep the tank full, so no condensation forms in it, it will last for years.

Thanks.......

12 months should be fine......I might even bump it out to two years. It to protect out environmental licence to operate of which is under scrutiny ATM the last thing we need is the generator not start due to dodges fuel.....don't think the authorities will see the funny side of it.

Are you any good at sizing a generator........two companies I have approached both suggest ed a 60kva but when our electricians questioned it one of them bumped it up to an 88kva which seems about right. The maths should be straight forward, would have thought the sales guys would have been all over it but they have given me little confidence.

Just I case you are

2 x 16kW submersible pumps
Max. running current 32amps
Soft start (currently DOL)
Delayed start I.e. One starts than the other

Weeds arse is on the line next time we discharge exceeding our licence agreement

[kreecha]

I have the same figure as Blknight. My figure is from my RAN experience.

[weeds]

From memory the book for the gensets that form up part of the field power distrribution system reccomedn that if the fuel isnt going to be used in 6 months that it be drained and replaced. however the onboard tanks are quite small and generally rely on daily refueling or 44 gallon drum feeders.

Thanks Dave...........the frequency doesn't overly bother us, by the sounds of it I could just transfer it into a forklifts/skid steer loaders

[Homestar]

Thanks.......

12 months should be fine......I might even bump it out to two years. It to protect out environmental licence to operate of which is under scrutiny ATM the last thing we need is the generator not start due to dodges fuel.....don't think the authorities will see the funny side of it.

Are you any good at sizing a generator........two companies I have approached both suggest ed a 60kva but when our electricians questioned it one of them bumped it up to an 88kva which seems about right. The maths should be straight forward, would have thought the sales guys would have been all over it but they have given me little confidence.

Just I case you are

2 x 16kW submersible pumps
Max. running current 32amps
Soft start (currently DOL)
Delayed start I.e. One starts than the other

Weeds arse is on the line next time we discharge exceeding our licence agreement

Yep, I size gensets as part of my current job.:)

A 60KVA would work, but it is the smallest unit that would do the job and would grunt getting the second motor away. The 88KVA is a much better choice - your Electrician was right to do that. Sales guys don't know as much as they think sometimes.... I am one now...:D. But I'm also a qualified Sparky who's been working only on gensets - both on and off the tools - for the last 18 years.

Oh, do you know what type of excitation the machine will have? There are 2 types - shunt and PMG. PMG excitation will give much better motor starting characteristics than a standard shunt excited unit. It will cost you another grand or so to go that way though. Also, some soft starters have issues with frequency changes like you see on a genset when a load is applied. It would pay to check the minimum and maximum frequency the starters will work at. VSD's work better off smaller genset supplies such as this.

[Blknight.aus]

the couple of times that I've had to setup FPDS and similar for prolonged standby some smart grease monkey usualy comes along with a valve to fit to the drain on the tank, a 44 with some custom bungs on it and a delivery nozzle for a gravity feed hose.

the 44 gets laid down on top of the genny, the delivery hose attaches to the small bung and sits at the bottom

the big bung has 3 ports on it and it goes uppper most on the 44 as its laying down.

1 comes from the bottom of the tank on the genny and has the facet pump on it. its the lowest port on the bung.

2. in the middle of the bungreturns from the drum to the tank breather hose

3. (highest) has the breather from the 44 drum.

while the genny gets its routine run up and test load the facet pump transfers fuel to the 44. the 44 cant overfill because ofport #2 returning to tank. when the test run and load banking is done the genny is refueled from the tanker truck and anyone with small gennys or appliances can come and get essentially unacounted fuel from the drum on top of the genny.

usually FPDS has at least 50% redundancy so the drum will get swapped across from one to the next as required.

and before anyone gets onto the fruad bandwangon

the diesel that used to come out of the tanks... used to get sent back at commonwealth expense for disposal.

[weeds]

Yep, I size gensets as part of my current job.:)

A 60KVA would work, but it is the smallest unit that would do the job and would grunt getting the second motor away. The 88KVA is a much better choice - your Electrician was right to do that. Sales guys don't know as much as they think sometimes.... I am one now...:D. But I'm also a qualified Sparky who's been working only on gensets - both on and off the tools - for the last 18 years.

Oh, do you know what type of excitation the machine will have? There are 2 types - shunt and PMG. PMG excitation will give much better motor starting characteristics than a standard shunt excited unit. It will cost you another grand or so to go that way though. Also, some soft starters have issues with frequency changes like you see on a genset when a load is applied. It would pay to check the minimum and maximum frequency the starters will work at. VSD's work better off smaller genset supplies such as this.

PMG........

Good point about frequencies, I will run it buy the contractor that is building the switchboard.

Currently have prices on a

Himoinsa and Olympian.......need to make contact with the the company that the an offshoot of caterpillar, cannot think of there name, the info is in my diary. My research tells me to buy a quality jap build engine/unit

If you can deliver to brisbane and interested in pricing one up shoot us an PM.

Cheers

[Homestar]

PMG........

Good point about frequencies, I will run it buy the contractor that is building the switchboard.

Currently have prices on a

Himoinsa and Olympian.......need to make contact with the the company that the an offshoot of caterpillar, cannot think of there name, the info is in my diary. My research tells me to buy a quality jap build engine/unit

If you can deliver to brisbane and interested in pricing one up shoot us an PM.

Cheers

PMG is Permanent Magnet Generator - it is a small generator on the back of the main alternator that supplies a separate power feed into the voltage regulator that is used as the drive for the exciter so you have less of a voltage dip when a large load is applied. The Sales guys from any genset company should be able to fill you in on the details.

I'm in the hire game, so unless you want a price for a long term rental unit, then I can't really help. I probably shouldn't go spruking my wares on here anyway.:)

We use a lot of FG Wilson units in our fleet - they are a Perkins powered unit and are reliable and competitively priced. Distributed by Allight in Australia. (No connection to them, Just another thought...:) )

[weeds]

PMG is Permanent Magnet Generator - it is a small generator on the back of the main alternator that supplies a separate power feed into the voltage regulator that is used as the drive for the exciter so you have less of a voltage dip when a large load is applied. The Sales guys from any genset company should be able to fill you in on the details.

I'm in the hire game, so unless you want a price for a long term rental unit, then I can't really help. I probably shouldn't go spruking my wares on here anyway.:)

We use a lot of FG Wilson units in our fleet - they are a Perkins powered unit and are reliable and competitively priced. Distributed by Allight in Australia. (No connection to them, Just another thought...:) )

thanks....heaps of help.

alllight, one of the companies mentioned FG Wilson.......

[d@rk51d3]

My employer bought an old de-commissioned hospital that has an emergency genset. It gets serviced every 6 months or so. During a recent power outage, the generator ran out of diesel. The boss rang the service company to see why they hadn't topped up the tank last month with the service, and they replied that they have never put fuel in.

So, this generator has been running on the same tank of diesel for 15-20 years. :D

[scanfor]

Weeds, I agree with Bacicat about sizing. 88kVA is the go.
My calculations are:

IF Weeds Arse is on the line, THEN Go for the bigger genset if in doubt
Discharge = NO, NO, NO
Money = Someone Else's (NOT Weeds')

I assume the pumps will do the swapover thing on mains operation, but in mains failure mode both may be required to operate at the same time (well staggered start anyway).
You also need to consider the pumps "fault" load - i.e if they're ragged when they try to start.

On the fuel age issue, we had diesel gensets for level crossings that did not have the fuel changed in the 4 years that I was working on them, and they tested fine every week.

[Owen]

FG Wilson are great units, I would look though to dropping a biocide in the tank to stop it growing bugs.

[d2dave]

I would tell the company that every six months would be a good idea and that I will happily dispose of the old fuel(in my LR tank):)

[weeds]

FG Wilson are great units, I would look though to dropping a biocide in the tank to stop it growing bugs.

Made contact with them but still haven't sent through a quote.....must be making plenty sales

[weeds]

I would tell the company that every six months would be a good idea and that I will happily dispose of the old fuel(in my LR tank):)

12 months Im thinking.....I value my job too much for the fuel to go anywhere but our mobile plant or dispose off

[Homestar]

Made contact with them but still haven't sent through a quote.....must be making plenty sales

I should have mentioned they can be a bit slow depending on who got your email. I'll zap an email to the Sales guy I know and tell him to get everyone to check their emails.:)

Did you send it to the generic sales@allightsykes.com email?

[weeds]

I should have mentioned they can be a bit slow depending on who got your email. I'll zap an email to the Sales guy I know and tell him to get everyone to check their emails.:)

Did you send it to the generic sales@allightsykes.com email?

It was a phone inquiry

[weeds]

I settled on a 110kva Cummins.........should be arriving tomorrow.

[Homestar]

Nice choice. :)