The XYL returned from a quick shopping foray this afternoon with the
latest magazine showing next week's offers which included a "Golden
Oldie" first seen two years back. Said Golden Oldie (the PGI 1200 A1),
presumably being priced for nostalgic reasons, is on 'offer' at the
original 129 quid price (their version of "Rollback Pricing" I'm
guessing).

Although remarkably cheap for an inverter genset even at the 30 quid
higher asking price than the later PGI 1200 B2 "Suitcase" generators they
were selling in the 2nd week of April this year, it has even more going
against it than the 99 quid B2 model which I'd assumed to be its
replacement and thus rendering the A1 model totally obsolete.

After checking out this video review on youtube:

https://www.youtube.com/watch?v=oclB_Uj7KX8

and taken another look at this one on the B2 model:

https://www.youtube.com/watch?v=JTTGvjbY8_s

which is worth checking out simply for the extremely informative
comments made by dean handley from ten months ago which would have saved
me so many return trips to finally track down a working PGI 1200 B2 some
seven weeks back, I have come to the conclusion that unless you want to
strip out the guts of the A1 and transplant them into a properly designed
enclosure of your own (whether portable "suitcase" or just a small brick
outhouse), or you simply want to use it for spares[1], I wouldn't bother
unless you're really desperate to get hold of a 1KVA pure sine wave
inverter generator having just missed out on April's bargain of the
decade in cheap inverter genset technology.

Having said that, it's still superior to a cheap open frame genset. Yes,
it may be almost as noisy but at least its 1KW of pure sine wave power
can be safely used with electronic kit and even old fashioned sine wave
UPSes, unlike normal generators using 'sophisticated' AVR control which
will grossly over-volt at the drop of a hat (leading current loads from a
few microfarad's worth of capacitance generally being all that's needed
ime to send a 2.8KVA 230vac generator going north of the 270vac mark!).

If you're looking for a cheap alternative to buying a few hundred quid's
worth of SLAs to boost the autonomy of a 1.5KVA or higher rated UPS by a
couple of hours, this could prove a more cost effective alternative,
especially as you can get a good 3 to 5 hours worth out of each gallon of
unleaded petroleum/gasoline you care to pour into its tank (5 to 7 hours
in the case of the PGI 1200 B2).

The only downside, of course, being the noise pollution if you don't
already have a suitable brick outhouse to minimise this and both secure
and run it safe from the CO poisoning and fire hazard risks presented by
such generators. In this regard, it's very little different to the 99
quid PGI 1200 B2 Lidl were selling just a mere 7 weeks ago. For static
use, the only downside is that extra 30 quid hit on your bank balance.

Even so, it's a remarkably cheap way to buy into a 1KW standby source of
pure sine wave 50Hz 230vac power. Now that I've replaced all the GLS
lamps (bar the set of four 35W 12v halogen downlighters in the shower
room) with LED lamps, I can keep all the lights on along with the fridge,
the freezer, the 4K smart TV, my IT kit and the CH with a mere 1KW of
standby power. Admittedly, only at a pinch and by careful power
management but if ever the need for sustained emergency power ever
arises, this is just exactly what anyone running off emergency power
would be having to do anyway.

I'd have preferred a 2KW inverter genset but not only are the cheapest
alternatives some four or five times as pricey, they'll burn through
emergency fuel reserves faster as well even when only providing the same
amount of power as the smaller genset. Limited emergency power is better
than no emergency power at all and even if I do push the boat out on a
quieter 2KVA inverter genset at a later date, at just 99 quid, I can
afford hang onto the Lidl genset as an emergency backup to the 2KVA
emergency backup genset. You can never have too many emergency gensets
when the price is *so* right. :-)

TBH, I'm quite amazed at the cheek of Lidl in trying to sell an inferior
version of the PGI 1200 B2 less than two months later and at an extra 30
quid to boot! Perhaps they're thinking that its "Retro Chic" cheap two
stroke portable genset looks are deserving of the extra 50 or 40 quid
over a more appropriate (IMHO) 80 or 90 quid price point. :-)

Major points of difference between the A1 and the B2 models a

The A1 uses a top mounted 4.2l pressed steel gravity feed tank prone to
leaking fuel during transportation. Fuel consumption rating at 2/3 power
output is 0.88l/hour from its 2.85hp 53.5cc engine (4.77 hours run time
on a tank of fuel). Considering the use of a gravity feed fuel system,
there's a surprising absence of a carburettor float bowl priming plunger
to assist cold starting.

The B2 uses a plastic (presumably shatter-proof) 4.5l side tank (which
reduces sloshing of its contents) feeding an engine vacuum powered fuel
lift pump[2]. Fuel consumption rating at 2/3 power output is 0.68l/hour
from its 2.04hp 53.5cc engine (6 1/2 hours run time on a tank of fuel).

The A1 is 200g lighter than the B2 (13Kg). Both produce the same total
sound power of 95dBW but the B2 claims to be 1.3dB quieter at the 1 metre
SPL test distance (80.2dBA).

Now that I have an actual class 2 SPL meter to test with, I'll be able
to confirm just how optimistic a claim this is for myself (give or take
1.5dB of metering error along with other environmental factors that make
such tests so less than 'scientific'). At least I'll be able to get base
line figures by which to gauge any attempts to quieten it.


[1] Afaict from pictures - unlike the potted inverter module in the B2,
two cermet trimmers do actually poke up out of the hard and shiny black
potting compound in the one used by the A1 making it amenable to
adjusting for manufacturer's calibration errors[3], assuming they haven't
switched over to using the same inverter part used by the B2 (probably
not since the A1 shown still only uses two LEDs to show status using
blink codes for normal/slight overload/full overload condition and
"Goodnight Vienna" whilst the B2 uses three LEDs).

[2] The only downside of using a fuel lift pump, aside from the extra
complexity over that of a simple gravity feed setup, is the need to spin
the engine over several times on the starter cord just to prime the fuel
line and the carburettor float bowl when starting from "Dry" (initial
commissioning run or else after a long lay up after letting the carb run
dry to minimise the risk of fuel gumming up the carburettor's jets during
periods of protracted storage).

In this case, it's best to crank the engine over leisurely 4 or 5 times
after turning the fuel feed on with the ignition still off and closing
the choke for the penultimate pull before turning the ignition on for a
full on pull of the cord to actually fire it up without needlessly
wasting energy on premature attempts to fire it up before there's even
any fuel in the carburettor float chamber.

Where more regular use (say every weekend) precludes any need to run the
carb float bowl dry, this won't be an issue. A single priming yank before
turning the ignition on and setting the choke should get it running on
the next pull of the starter cord.

[3] I discovered when testing with a 900W toaster and a bunch of 150W
incandescent lamps and a few other ses lamps of various wattages that the
inverter signals overloading at the 980W mark according to my digital
watt meter. I was a little disappointed at discovering this, especially
in view of the fact that it would cheerfully run a 1200W test load not
for the mere 5 seconds claimed but a full half minute every time before
shutting the inverter down.

I realise it's just possible that it's been calibrated to detect
overload at exactly 1001 watts and my watt meter is merely under reading
by 2% of the +/-3% allowance of its rated measurement tolerance. Still,
I'd have hoped they would have erred a little more on the positive side
of the tolerance range with their overload setting point, say 1050W
before sensing an overloaded state.

This is how I came to discover the complete absence of any means to
adjust the output voltage setting or the current overload point to
correct such a parsimonious setting. I guess I'll have to do some cross
checking with my other "Kill-A-Watt" meter and the analogue watt meter
before deciding whether to buy another PGI 1200 B2 the next time they're
on offer from Lidl to do a "Pick 'n' Mix" swap out to get the inverter
genset I so richly deserve.

--
Johnny B Good

On Sat, 26 May 2018 02:34:31 GMT, Johnny B Good wrote:

The XYL returned from a quick shopping foray this afternoon with the
latest magazine showing next week's offers which included a "Golden
Oldie" first seen two years back. Said Golden Oldie (the PGI 1200 A1),
presumably being priced for nostalgic reasons, is on 'offer' at the
original 129 quid price (their version of "Rollback Pricing" I'm
guessing).

After Mr Plowmans post on laser levels and this one I'm glad that
there isn't a Lidl where I normally go... Aldi is OK but doesn't have
the range of wallet threatening "big boys toys" that Lidl does. B-)

Both produce the same total sound power of 95dBW but the B2 claims to be
1.3dB quieter at the 1 metre SPL test distance (80.2dBA).

Hum those figures don't add up 95 dBW (aka 95 Lwa) is 87 dBA @ 1m or
70 dBA @ 7 m (7 m being the "industry standard distance" for
gensets). I think that's the same as the mower.

I have an open frame 2.2 kVA, non-invertor, diesel set, now that is
fing noisey, difficult to hold a conversation next to it noisey!
However it is electric start(*) and uses about a litre an hour. But
at about 60p/l less than petrol as it can use red diesel.

I've used a couple of Honda EU20is, linked, and they where really
quiet, audible but not overly so as reflected by the quoted 52dBA @
7m (89 Lwa).

(*) In theory so that SWMBO'd should be able to start it. Probably
never happen as it's also rather heavy even though it's mounted on a
4 wheel flatbed trolly. She'd never manage to pull start it far to
complicated a process. Release the compression, spin it up on the
cord, drop in the compression and hope it fires... I think your
suposed to be able to set the engine and compression release so that
one pull does the complete cycle and off it goes but if you get it
wrong and pull into compression it don't half jar your arm. B-)

--
Cheers
Dave.

On Mon, 28 May 2018 22:07:10 +0100, Dave Liquorice wrote:

On Sat, 26 May 2018 02:34:31 GMT, Johnny B Good wrote:

The XYL returned from a quick shopping foray this afternoon with the
latest magazine showing next week's offers which included a "Golden
Oldie" first seen two years back. Said Golden Oldie (the PGI 1200 A1),
presumably being priced for nostalgic reasons, is on 'offer' at the
original 129 quid price (their version of "Rollback Pricing" I'm
guessing).

After Mr Plowmans post on laser levels and this one I'm glad that there
isn't a Lidl where I normally go... Aldi is OK but doesn't have the
range of wallet threatening "big boys toys" that Lidl does. B-)

Both produce the same total sound power of 95dBW but the B2 claims to
be 1.3dB quieter at the 1 metre SPL test distance (80.2dBA).

Hum those figures don't add up 95 dBW (aka 95 Lwa) is 87 dBA @ 1m or 70
dBA @ 7 m (7 m being the "industry standard distance" for gensets). I
think that's the same as the mower.

I see references to the 7m SPL dBA figure in generator youtube vids (or
as the Yanks call it "the 23 foot SPL reference distance"). I did query
those figures in my mind but since a class 2 SPL meter is only able to be
calibrated to within +/- 1.5dB accuracy anyway, it didn't seem to be a
significant enough discrepancy to get all hot and bothered about.


I have an open frame 2.2 kVA, non-invertor, diesel set, now that is fing
noisey, difficult to hold a conversation next to it noisey! However it
is electric start(*) and uses about a litre an hour. But at about 60p/l
less than petrol as it can use red diesel.

That's not only a useful saving, it's also less of a long term safe fuel
storage problem. The penalty for going for the affordable open frame
option being the horrendous noise pollution if you can't run it in its
own little brick outhouse to keep the noise level in check.


I've used a couple of Honda EU20is, linked, and they where really
quiet, audible but not overly so as reflected by the quoted 52dBA @ 7m
(89 Lwa).

If I've done my quick 'n' dirty calculations correctly, I reckon that
would equate to a 1 metre SPL of 66dBA. A significant reduction on the
80.2dBA quoted for the PGI 1200 B2 (which will be the no load eco
throttle idling condition - idling with eco-throttle disabled raises the
level another 10dB or so and loading it up with a 980W load will raise
that by yet another 6dB or so).

Those Honda suitcase inverter gensets are remarkably quiet but I can't
justify shelling out an extra 800 quid plus for one. Since it's not so
much for day trips out into the wilds and more a solution for a minimum
level of emergency home power come the next winter (or the ones after
that), I feel a more optimal solution is to build a little brick outhouse
behind the garage in which to both secure and operate it without creating
a noise nuisance for both myself and my immediate neighbours.

At least this way, if I do opt for a "cheap" 2 or 3 KVA inverter genset
at a later date, I can forego the quietness of a genuine Honda inverter
genset by making sure there's ample space for an even larger open frame
genset inside. Whatever the upgrade, one thing's for certain, it won't be
a conventional genset destined to go the way of the Dodo - only an
inverter type will do the job.


(*) In theory so that SWMBO'd should be able to start it. Probably never
happen as it's also rather heavy even though it's mounted on a 4 wheel
flatbed trolly. She'd never manage to pull start it far to complicated a
process. Release the compression, spin it up on the cord, drop in the
compression and hope it fires... I think your suposed to be able to set
the engine and compression release so that one pull does the complete
cycle and off it goes but if you get it wrong and pull into compression
it don't half jar your arm. B-)

Tell me about! It's bad enough pull starting a diddy 53.5cc single
cylinder four stroke when I'm as unfit as I am. :-( It's the reason for
my describing in detail my "Dry starting" routine.

Wishing this inverter genset had electric start got me to wondering
about add-on electric starter upgrade kits to replace the recoil starter
cord. I know some of the larger open frame generators can be upgraded to
electric start (retaining the pull starter cord) but they either need a
starter ring gear fitting or else they already had a starter ring to
begin with but were simply not fitted with the starter motor, solenoid
and battery to provide a cheaper option to their customer base.

Then it hit me! Inverter gensets already have the core part of a
permanent magnet brushless DC motor disguised as a multi-pole three phase
PM alternator. :-)

All it would need is a starter battery and a DC brushless motor
controller module add-on to neatly upgrade an inverter genset to electric
start. Better still, the electronics could all be integrated into the
micro-processor controlled inverter module itself, only requiring the
installation of a small starter battery (say a 7A SLA or its smaller
lightweight Li-ion equivalent).

TBH, this is such a "No Brainer" idea, I'm surprised none of the quality
names in suitcase inverter generator manufacturing aren't already using
this technique in their latest "Must Have" product lines to 'freshen up'
market demand. Perhaps they have and I just haven't noticed.

Anyhow, this got me to ruminating on the possibilities such a revamping
of the old "Dynastart"(tm) could provide. For starting purposes, you
wouldn't need to use the full 400 volt (200v for a 120v generator),
probably just a quarter of output voltage would suffice. However, using a
DC-DC converter to generate the full voltage from a 12 or 10.8 volt
starter battery would allow an even more frugal eco-throttle setting to
be used without fear of stalling the engine on pick up of a sudden
increase in load.

Then I thought, "Why stop there? Why not combine the function of an
inverter genset with that of a line interactive UPS?". It's quite thought
but with a lightweight Li-ion battery pack it need only be a few pounds
heavier than a pull start inverter genset since the battery would only
need to provide a few minutes of autonomy for the UPS function and from a
battery that demonstrates only a fraction of the Peukert effect that's
routinely relied upon to protect UPS SLAs from excessive DoD.

It's surprising what you can come up with when you let your mind wander
where it will. :-)

--
Johnny B Good

Johnny B Good wrote:


Then it hit me! Inverter gensets already have the core part of a
permanent magnet brushless DC motor disguised as a multi-pole three phase
PM alternator. :-)

All it would need is a starter battery and a DC brushless motor
controller module add-on to neatly upgrade an inverter genset to electric
start. Better still, the electronics could all be integrated into the
micro-processor controlled inverter module itself, only requiring the
installation of a small starter battery (say a 7A SLA or its smaller
lightweight Li-ion equivalent).

TBH, this is such a "No Brainer" idea, I'm surprised none of the quality
names in suitcase inverter generator manufacturing aren't already using
this technique in their latest "Must Have" product lines to 'freshen up'
market demand. Perhaps they have and I just haven't noticed.

Would make it more expensive for the vast majority of customers for whom
these small generators are just for emergency or possibly camping. Add to
weight as well and if someone isnt healthy enough to pull start a small
generator they may not wish to carry something heavier.
Human nature being what it is a lot of people would forget about running
the generator for years and come the first emergency find the battery flat.
Thinking outside the box many who are technical or savvy enough to own a
generator will already have a battery and motor in the form of a cordless
drill, now if you had an accessible bolt head connected to the end of the
crankshaft that could take a socket or hex drive you could use one a
starter motor though the need to be a bit deft when it fires may be an
obstacle .


GH

On Tue, 29 May 2018 07:53:50 +0000, Marland wrote:

Johnny B Good wrote:


Then it hit me! Inverter gensets already have the core part of a
permanent magnet brushless DC motor disguised as a multi-pole three
phase PM alternator. :-)

All it would need is a starter battery and a DC brushless motor
controller module add-on to neatly upgrade an inverter genset to
electric start. Better still, the electronics could all be integrated
into the micro-processor controlled inverter module itself, only
requiring the installation of a small starter battery (say a 7A SLA or
its smaller lightweight Li-ion equivalent).

TBH, this is such a "No Brainer" idea, I'm surprised none of the
quality
names in suitcase inverter generator manufacturing aren't already using
this technique in their latest "Must Have" product lines to 'freshen
up' market demand. Perhaps they have and I just haven't noticed.

Would make it more expensive for the vast majority of customers for whom
these small generators are just for emergency or possibly camping. Add
to weight as well and if someone isnt healthy enough to pull start a
small generator they may not wish to carry something heavier.
Human nature being what it is a lot of people would forget about running
the generator for years and come the first emergency find the battery
flat.

You forget that the 'Early Adopters' will always pay for the development
costs which in this case won't be particularly high - it's mostly a
little bit of extra 'silicon' in an existing inverter/controller module.

The manufacturers always 'Make Hay Whilst The Sun Shines' when offering
such enhancements to an existing product line. Eventually, after 'The
Tooling Costs' have been well and truly amortised and 'They're all doing
it', competition will force the pricing to a more reasonable mark up. In
some cases, the savings made in upgrading the manufacturing to serve an
expanding mass market will allow them to increase their profit margins
whilst still offering cheaper prices.

As for the weight increase, this will pretty well be down to that of a
7AH SLA at most. If the longer lived lighter and more compact Li-ion
equivalent is employed, it's likely to be just half a Kg on a 13 to 18Kg
genset.

Thinking outside the box many who are technical or savvy enough to own a
generator will already have a battery and motor in the form of a
cordless drill, now if you had an accessible bolt head connected to the
end of the crankshaft that could take a socket or hex drive you could
use one a starter motor though the need to be a bit deft when it fires
may be an obstacle .

Yep! I've seen plenty of such youtube vids demonstrating the
technique. :-)

--
Johnny B Good

On Tue, 29 May 2018 12:02:46 +0000, Johnny B Good wrote:

On Tue, 29 May 2018 07:53:50 +0000, Marland wrote:

Johnny B Good wrote:


====snip====


Thinking outside the box many who are technical or savvy enough to own
a generator will already have a battery and motor in the form of a
cordless drill, now if you had an accessible bolt head connected to the
end of the crankshaft that could take a socket or hex drive you could
use one a starter motor though the need to be a bit deft when it fires
may be an obstacle .

Yep! I've seen plenty of such youtube vids demonstrating the
technique. :-)

And, I meant to take the opportunity to also mention the many youtube
vids of alternators being converted to motors and motors into alternators
by the simple expedient of hooking up the appropriate DC Brushless
electronics package to the former and the appropriate rectifier/regulator
electronics package to the latter.

Whirly magnetic bits and copper wound ironmongery at the heart of both
machines are quite interchangeable in function with the appropriate add-
on electronics package. It's such a no-brainer option, I'm amazed the
starter function at least isn't already built into the inverter module to
make provision for an optional extra electric starter feature, merely
requiring the addition of a small starter battery to fulfil the "Value
Add" of the more expensively specified model variant.

--
Johnny B Good

On Tue, 29 May 2018 07:53:50 +0000, Marland wrote:

Johnny B Good wrote:


====snip====

Thinking outside the box many who are technical or savvy enough to own a
generator will already have a battery and motor in the form of a
cordless drill, now if you had an accessible bolt head connected to the
end of the crankshaft that could take a socket or hex drive you could
use one a starter motor though the need to be a bit deft when it fires
may be an obstacle .

Unfortunately, with the parkside PGI 1200 B2 inverter genset, the
inverter module blocks such access to that end of the engine shaft and
there's no easy way to get around it short of transplanting the guts into
another larger carapace that would allow me to alter the layout to suit.

The only possibility for adding an electric start feature would be
something like a Radio Controlled dc brushless motor electronic speed
controller (ESC) module rated for 42 or 48 volts operation[1].

Although this is only an eighth of the normal alternator output voltage
at the circa 4000rpm eco-throttle idling speed of the engine, it may
still prove sufficient for starting since it represents an equivalent
cranking speed of 500rpm (assuming no I squared R losses), say 350 to
400rpm in practice which may be just sufficient to fire it up. IIRC,
yanking the starter cord vigorously sounded to me like 5 pulses per
second's worth of engine cycles, equating to a cranking speed of 10 revs
per second or circa 600rpm - probably 350rpm for two or three seconds
could stand in for the half second's worth of starter cord effort.

The only extra complication in this case, compared to the more usual car
alternator to BLDC motor conversion exercise, being the need to rapidly
isolate the ESC module before the alternator voltage output exceeds the
maximum breakdown voltage of its motor drive transistors as the engine
runs up to speed.

Judging from the ESC modules used by the RC hobbyist fraternity, there
should be ample space to fit the necessary electronics required to run
the PM alternator as a starter motor. The question is, Can I cobble up my
own version of an already proven technological solution at an economical
price?

There's absolutely no question that it *can* be done but at what cost?
Even if I can get hold of a cheap 72 or 84 volt programmable ESC module,
I'd still have to solve the problem of providing battery power to
generate the required 72 to 84 volt rail and incorporate a suitable
charging module to replenish my chosen battery option.

Stringing twenty 18650 cells in series doesn't seem a sensible option to
create a 75v battery so that leaves me with the choice of either a 12v SLA
or a three cell 11.25v Li-ion battery pack and a simple DC-DC converter
to multiply the battery voltage by a fixed step up ratio (a basic, no
frills square wave driven high frequency step up transformer converter
offers the most efficient option, circa 98% conversion efficiency).

It would be nice if it could all be done with just a 12v supply to the
alternator come starter windings but modifying the alternator stator
with additional low voltage delta connected windings is out of the
question and, even if incorporated by design, would compromise its
performance as a generator to a greater or lesser degree anyway.

Quite frankly, the only sane way to provide an electric starter feature
to any inverter genset is to incorporate the necessary BLDC motor ESC, HV
converter and battery charge management modules into the existing
inverter module where the starter battery can also be utilised to improve
the eco-throttle performance, making the eco-throttle switch redundant,
the elimination of which might well pay for the additional 'silicon' used
in the inverter module (if not the HF ferrite step up transformer used by
the HV converter module).

[1] Having googled for the cheapest source of ESC modules (RC units), the
highest voltage ratings are limited to 6 Li-ion cell's worth, 22.5v
(probably a maximum of 24v in reality) so a cost effective electric start
modification via the RC Hobbyist supplies market doesn't look quite as
promising as I'd hoped (cranking speed limited to little more than 200rpm
according to my calculation - in the 115v 60Hz inverter case, 400rpm
which might just suffice in that case).

The next option is with disability scooter BLDC ESC modules (they can go
right up to 72v (84v max) but the 48v modules are more common and more
expensive than a cheap 'n' cheerful 6S RC BLDC ESC module). It looks like
I'd have to custom design and build my own ESC module if I want to
upgrade to electric start.

Unless I can track down a still active news group that relates to such
electronic projects, it doesn't look very doable. Trying to track down
web fora that go beyond the business of describing car alternator to BLDC
go-kart motor conversion project youtube vids looks rather a hopeless
task. :-(

--
Johnny B Good

On 29 May 2018 07:53:50 GMT, Marland wrote:

now if you had an accessible bolt head connected to the end of the
crankshaft that could take a socket or hex drive you could use one a
starter motor though the need to be a bit deft when it fires may be an
obstacle .

Better to fit a spiral drive as used on starting handles.

--
Cheers
Dave.