I fully concur except I never even bothered with the additional weight of an
analogue Tacho. I have 250 hours now with the EIS and it has been excellent.
I recently fitted a prototype Constant Speed controller to my Arplast
propeller. This works in parallel with the EIS and both instruments give
digital RPM readout. The new controller did not interfere with the EIS and I
didn't have to change anything.
I am connected with the EIS selling it in the UK but that doesn't stop me
---From singing its praises. The EIS is not as flash as some new bits of kit
but I have few complaints from customers and the support from Greg is always
excellent.
Jerry
Jerry@ban-bi.com or LTS@avnet.co.uk
www.Ban-bi.com or www.avnet.co.uk/touchdown
----- Original Message -----
From: "John & Paddy Wigney" <johnwigney@worldnet.att.net>
Subject: RPM readout
> Dear Europaphiles,
>
> I would like to give my comments on RPM readout based on about 100 hours
> experience on my mono XS with a 912S engine. I installed an EIS panel (see
> below) which has a digital RPM display and I also installed a Rotax R629M
2 inch
> analog tachometer since I believed that I would use the analog as the
primary
> tacho indication. Before flying the plane, I belonged to the school which
> believes that analog indication is the only way for quick understanding.
> Interestingly I had spoken to Greg Toman at Grand Rapids Technologies who
make
> the EIS unit on another matter and he explained that I would stop using
the
> analog gauge and would rely on the digital. I did not believe him, but he
was
> right. The EIS refreshes very rapidly, at least as quick as the needle
swings,
> and it is always extremely accurate. For example, I have a WhirlWind
constant
> speed prop and in cruise, I can adjust the RPM up or down within 10 rpm by
using
> about a quarter turn of the prop vernier. I find now that I never refer to
the
> analog tacho.
>
> I should explain that I have no personal or business relationship with EIS
but
> for those considering panel design,I can highly recommend the EIS 2000
unit. It
> has various pages which can be accessed as necessary and a default
"favourite"
> page where I display :-
> RPM
> Oil temperature
> Oil pressure
> Fuel pressure
> Fuel flow (this is an optional extra item)
> CHT
> EGT
> All the outputs can be set with high and/or low alarms which flash a large
red
> lamp.
>
> The other engine outputs available on my unit on the other pages are :-
> Total fuel remaining. (Reset at every fuel fill)
> Endurance time (Calculated by fuel remaining divided by current fuel flow)
> Voltage
> Coolant temp
> Timer for current flight. (This resets automatically)
> Total engine time. (Equivalent to Hobbs time)
>
> Finally, analog gauges do have their place. I do use a Manifold Pressure
analog
> gauge to set my cruise throttle opening.
>
> Cheers, John
> N262WF
>
> Fred Fillinger wrote:
>
> > Nigel Charles wrote:
> > > ...
> > > An rpm gauge is the only engine gauge which I feel needs analogue
display.
> > > Ironically these are often the ones which need the most setting up.
Mine
> > > overeads by 200rpm at 5800rpm.
> >
> > RPM should be the most suspect of all. Convenient to think digital is
> > more accurate, but you can't just count pulses - accurate to within
> > parts per million, but at even 50RPM resolution, the display update
> > rate is unacceptable. Other approaches then become dependent on
> > mechanical and other issues in the stator ass'y from whence come the
> > pulses, with accuracy attainable with $$, unless the higher price is
> > just more profit. Same for analog gauges. Digital RPM checkers which
> > read optically are very accurate and affordable. Borrowing or buying
> > one of these is arguably a must! Or a freq counter from Radio Shack
> > and do the math.
>
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