Author Topic: Voltage drop under load  (Read 1976 times)

Johndoh

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Re: Voltage drop under load
« Reply #105 on: October 21, 2018, 10:45:56 PM »
For my need it in a hurry with max output gennies, I set rpm to between 60 to 63hz, volts to 240... These are the little portables that I lug round the plot to do the odd bit of electrical needed in a remote corner type work... they seldom run more than an hour or two at a time, but are run hard...

The bigger, less portable standby units, I normally clock to 51hz unloaded, 230V, and they run at a lower percentage of total output, but much, much longer periods....

Both ways they seem to last well... but to run hot and fast and heavy for long ain't a good idea in my book....

Cheers
Ed
Hi Ed
Thanks for the info all this stuff is stored for future reference, I will speed it up slightly tomorrow only need 60 more rpm. Power was off for an hour this evening and I ran a few lights and the television off it, wife didn't complain about flicker either. Now a question Ed do you know how I could find out the total output of the alternator using a multi-meter?
Thanks
Paul
It is better to light a candle than to curse the darkness

EdDee

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Re: Voltage drop under load
« Reply #106 on: October 23, 2018, 12:56:09 PM »
Hey JD,

Not easy.... Need 2... one measuring current, the other voltage....Multiply the readings to get VA.... add up your totals every second or two, do it for an hour, you get KWH ....

Or....

Buy a cheapie VA meter off fleabay and throw away the pencil!

Cheers
Ed
12/1 750RPM/9HP Roid 5kVA- WMO Disposal/Electricity & Hot Water Gen
12/1 650RPM/8HP Roid 4.5kVa - Demon Dino
Chinese Yanmar - Silent Runner with AutoStart
Classic Komatsu 1963 Dozer/Fergusson 35 Gold Belly ...
Bikes,Cars,Gunsmithing & Paintball...Oh yes, a 5Ha open air Workshop to play in!

glort

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Re: Voltage drop under load
« Reply #107 on: October 23, 2018, 02:19:42 PM »

Buy a cheapie VA meter off fleabay and throw away the pencil!

How would you do it that way Ed?
Just load the thing up to overload and read off the max output?

EdDee

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Re: Voltage drop under load
« Reply #108 on: October 23, 2018, 03:41:24 PM »
Yep, that's pretty much it.... Load to start of black, make note of V/A/Kw.... Load to start of blue, note same..... A quick look at the exhaust emissions from a distance tells you approx how hard its running....except at night.....then you can only tell if its running hard if the exhaust glows orange....

Lol
Ed
12/1 750RPM/9HP Roid 5kVA- WMO Disposal/Electricity & Hot Water Gen
12/1 650RPM/8HP Roid 4.5kVa - Demon Dino
Chinese Yanmar - Silent Runner with AutoStart
Classic Komatsu 1963 Dozer/Fergusson 35 Gold Belly ...
Bikes,Cars,Gunsmithing & Paintball...Oh yes, a 5Ha open air Workshop to play in!

glort

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Re: Voltage drop under load
« Reply #109 on: October 24, 2018, 02:05:07 AM »

One of these Meters Ed suggests Paul would be handy on your control box anyway. I have several of them.

there are a couple of types, the ones that are relatively low current that run direct through the meter and the others which take up to 100A I think it is and have an inductive pickup you put round one lead.  I was looking at one of mine this morning.  Inverter reported wattage was 27W different to the meter on a 3.6 Kw output. better than 1% is good enough for me but for all I know, the meter could have been more accurate than the inverter. 

Another hand feature of the things is to see how much power in total you have used.  this is very handy for my solar because not all my old inverters have this feature and some re set once the sun sets so if I'm a bit late because it's cloudy or something, I don't know how much power that unit made for the day. Not that many people would worry but like I said, I have no life so have time to pay attention to these things!  :0)

These are the ones to get:

https://www.ebay.com.au/itm/AC-80-260V-LCD-Digital-0-100A-Volt-Watt-Power-Meter-Ammeter-Voltmeter-CT/262893099112?hash=item3d35a65868:g:lk8AAOSwTM5YxmA4:rk:4:pf:1&frcectupt=true

Bought a lot of stuff off that seller and found them to be very good and reliable as well as being the cheapest if not only cents away from being the cheapest.
You can remote mount the sensor as well by just extending the leads and running them back to the meter.  Note, you only run ONE wire through the middle of the sensor and there is no electrical connection which is a good feature.  I have a couple of these set up in a jiffy box that I can just plug in to different things and see what they are doing. the logging feature of power used is handy to see how much power the Fridge or the heater in the biogas digester is pulling per day as well as the instant draw.  You can also see how heavy the current different things like water heaters are pulling or how much your solar inverter or generator is pushing back.   :0)

You could also use a clamp meter but these things are generally cheaper and you get more readouts and the logging where you can measure over a period of time. And the batteries don't go flat when you leave them on.... as they are supposed to be.

Johndoh

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Re: Voltage drop under load
« Reply #110 on: October 24, 2018, 09:55:34 AM »
Thanks Glort more stuff to think about more toys for me! I was looking at a Robin EY20 generator yesterday needs some work but interesting if I can get it cheap. I know I dont need it but I never had a Robin engine before something to play with over the winter.
It is better to light a candle than to curse the darkness

glort

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Re: Voltage drop under load
« Reply #111 on: October 24, 2018, 10:25:57 AM »

Robins are great engines. Made by Fuji Heavy Industries, AKA Subaru.
Far as petrol Gennys go, these would be a top shelf Choice.

Personally I think it's a good idea to have a petrol and a Diesel Genny. Most people have a petrol car or there is one close by and even a 1/4 car tank will power a genny for a good while.  Only thing is if you are not going to use them for a while, drain the carby and the tank and then give them a rinse with some petrol that's had a good amount of 2 stroke or engine put in it to stop any corrosion.
Also drain the sump and refill with fresh oil.

You could also get a gas carby like I linked somewhere recently so you could have the option to run on LPG as well.

We are going to start sounding like a bunch of those goofy preppers soon.  The minute anyone starts talking about "Bug out vehicles" I'll be bugging out of here.
How people think they are just going to cruise down the highway to their bunker or whatever in a dire emergency when in most places an hour trip down the road takes you 3 at holiday time just does my head in. Of course the other side is, you are going to stack your house with Food, water, fuel and have the lights on at night while all the neighbors around you sit in the dark and starve.
From there, if they do come wanting food etc and try to take it, you are going to have a shoot out with them too keep whats yours.

YA!

There's more than one born every minute, there's a whole pile of them and they breed as well!  :o

Johndoh

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Re: Voltage drop under load
« Reply #112 on: October 24, 2018, 11:02:22 AM »
Thats splendid news about the Robin. Seller said he put a new carb on it but it needs "adjustment" I checked and new carbs are pretty cheap and readily available. Of course people attempt repairs on things they shouldn't touch so if I get it might be a simple fix. Glort you repaired lawnmowers I sometimes buy them in winter and do them up, its a little source of income. The amount of mowers with the carb gummed up and all the little springs missing on the carburettor linkage is amazing. These simple engines are a big challenge for some people.
It is better to light a candle than to curse the darkness

glort

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Re: Voltage drop under load
« Reply #113 on: October 24, 2018, 12:44:28 PM »

You are dead right there.
I used to really like doing the little engines. To sound cliche, it was like each one had it's own little story when you opened them up.  Some were just worn but appeared cared for, some had been destroyed by people without a clue.
I don't know how many I picked up at the tip, brought them home and with the most minor of " repairs" , ran perfectly.  I got 3 over time that had obviously been rebuilt very recently.  I remember one was missing the sparkplug and very dirty. I used to do them in batches so I washed a load of them down and started tearing into them. I pulled this one apart and when I got into it, I couldn't believe it. I wasn't sure if it had even run but had been fully recoed.
There was still grease in the roller bearings.

Put it back together, put a plug and fuel in it and off it went.  Sold it to a Neighbour whom had the thing 10 years last time I saw it.

On the opposite end there were a few that had been recod not too long before but being 2 strokes, some twit had not put oil in the petrol.  Looking at engines that have welded themselves together  through lack of oil, 2 or 4 stroke is nit a pretty sight.
I mainly did 2 strokes which were a locally made brand because parts were cheap and plentiful and I could tear them down and have them rebuilt in an hour and running again. 

The only 4 strokes here at the time were Hondas that never went wrong and those POS garbage Briggs things.  I hate them with a passion and always will! Cheaply made poor quality CRAP!  We would tear bran new ones down before giving them to contractors and find problems with them. A  real common one was flashing in the castings almost blocking the inlet or exhaust port.  Carb linkages that were out of wack were another one not to mention those horrid " Pulsa jet" and the like carbs which were briggs own nightmare creation.

What morons would  make an engine with aluminium bores and steel piston rings?  Didn't do a lot of them as repairs or rebuilds as they simply were not worth it.  You could literally buy a set of pistons and rings for a 350 Chev cheaper than buy a rebuild kit for a briggs from our supplier.  As mate pointed out, a Piston for a briggs cost more than a set of 6 Pistons for a local brand car.  Crazy.

I liked 2 strokes best but didn't like doing chainsaws. Still don't . Too tight and fiddly for my shrek hands and fingers as my daughter calls them.  My own chainsaw is sitting up the back now and needs the fuel lines replaced. Bought it months ago but been putting the job off. Got the thing out the other day and made a start but took me about 2 min to decide I wasn't in the mood for frustration so it's sitting right in the shed door for me to trip over and be motivated to do it.  Brush cutters were OK, not much to them and they come apart easy.  Did a fair few 2 stroke bikes as well. Mainly Dirt bikes but a few yamaha RD 2 and 350s which were the hot ticket then. Bikes were ok just doing the top end but I didn't like pulling the engines out and mucking wioth everything else. Too complicated for my liking even though I could do it.  Usually forget something and have it all buttoned up then spot one gear or spring sitting on the bench. Aggghhh!  With the top end there was nothing to forget.

When ethanol laced fuel came in here, that was a good revenue raiser for small equipment places.  Sucks the water clean out the air and condenses it in the tank or fuel bowl.   
We'd clean them out, always a blocked main jet and gunk in the float bowl and tell them it was fuel and to use proper stuff not the Ethanol laced  but some listened and happily, a lot did not. They would get miffed about the problem recurring but we'd say how did it go when you picked it up, perfect, then it wasn't a bad repair was it?  They would come back so obviously knew it even if they didn't want to admit it.


I often think of doing those things. I really enjoyed it.  I had my white collar upmarket business which made me heaps of money but I liked doing stuff with my hands, getting filthy and bringing these things back to life.  Often I'd be finished with  clients, take off the shirt jacket and pants and be up the shed covered in grease and crap.  Few hours up there, back inside for a shower and a scrub and back to  being all professional again.  My secretary thought I was nuts. Occasionally Clients would drop in without an appointment and see me in mechanic mode but it was never a problem, in fact I used to say was a great rapport builder with the blokes.  Sometimes I'd just stay there at night and not finish till midnight. I found it relaxing and was nice to be up the back with teh doors open on a warm summer night and summer was obviously the busy time.  The late hour Never stopped me firing anything up for a test run though!

 Smartest thing I ever did was buy another house to run the business from instead of renting a shop.  Had so many upsides it wasn't funny. Had huge garage, just as big a workshop and a great house for the business.  Pool in summer was also great when the kids were young and we could sleep there weekends as well.  We never had a party at home either, always there because it was so much bigger and better for entertaining. 
 Of course the fact i sold it for exactly $1M profit 20 years later wasn't a downside either! 
I made  real good money with my mate doing those mowers and engines which was all in my spare time between clients or just as something to chill out doing. 

That was a real good time in my life.
 I'd give a lot more than a million now to go back to the way things were then.  :(









ajaffa1

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Re: Voltage drop under load
« Reply #114 on: October 24, 2018, 12:58:21 PM »
Hey Glort, there is still money to be made in servicing small engines. There is a company in Hongkong called Farmertek, they make very good reproduction parts for Stihl and Husqvarna machinery. A new cylinder, piston, crankshaft, all the gaskets and etc for a 48 cc chainsaw was under $100 delivered. Replacement chainsaw around $1000

Bob

Johndoh

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Re: Voltage drop under load
« Reply #115 on: October 24, 2018, 01:12:37 PM »
I always find myself strangely attracted to Briggs side valve engines! Good Honda lawnmower engines are easy to get probably because the frames are rotten, nobody ever cleans them and they rust from underneath. The engines don't fit the aluminium mower bodies that the Briggs engines fit. My mower is a really old CastelGarden with an old Briggs Quantum side valve engine. It needs valve stem oil seals this last 5 years poor compression and smokey I really have to fix it for next year. It's got the wrong carburettor and cables made from old bicycle brake cables. You'd never see a 2 stroke mower here apart from on a hover mower. I know the Briggs OHV engines are crap so Im now on the hunt for a 5hp Quantum side valve
It is better to light a candle than to curse the darkness

glort

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Re: Voltage drop under load
« Reply #116 on: October 24, 2018, 01:39:04 PM »
A new cylinder, piston, crankshaft, all the gaskets and etc for a 48 cc chainsaw was under $100 delivered. Replacement chainsaw around $1000


Wow! That's good markup potential. No way I could do chainsaws now. My eyesight isn't good enough and wearing glasses where I need them close up but can't see a thing distance with them frustrates me for a start. My fingers aren't as nimble as they used to be and my patience is non existent.
I'd be launching the things 50M down the driveway onto the road.  :embarassed:

Quote
Good Honda lawnmower engines are easy to get probably because the frames are rotten, nobody ever cleans them and they rust from underneath.

The local built ones here with the 2 strokes all had aluminum base plates. Never rusted out but after 20-30 years use which was not uncommon, could get worn through from all the sand and rocks abrading them.  Most people would just drill some holes and rivet a patch over the things as it was usualy the sides that wore through.

I did hot up a couple of 5 Hp IC briggs motors which werw SV engines.  The ones with the aluminium casing but cast iron sleeve that were the higher spec industrial series.  No plastic flywheels or camshafts in those things and a full 1" crankshaft.
Ported the hell out of those, shaved the heads and a few other little things. later on you could get proper performance parts for the things as they were used in the US for Jnr Drag races and other kart racing.  from what I have seen they have largely been overtaken now by the " Predator" type  Chinese engines imported by the likes of Hava fright  and other US stores.  Aftermarket suppliers like Go power sports do every performance mod imaginable  from cams to heads, carbs, valves and casings.  Not hard now to get 20 HP+ out of a 5 hp block and 60Hp_ out of the big twin 20 Hp engines.

Don't know if anyone still makes side valve engines not. think they are a thing of the past well and truly.

Subaru have had a line of Fuel injected engines for some time now as have some other makers and now the chinese are getting onto them as well.  they will all have to go this way I imagine to meet the polloution standards of the US and other places with tight emission regs.
Still probably wont beat the performance of an aftermarket and oversize Tillotson carb on one or a mikuni.