Monitoring all 4 CHT/EGT

[Darick]

My first thought when considering the MGL Velocity engine monitor, is that you can't monitor all CHT/EGT since it only has four inputs. It seems many folks use this set up for the AeroVee so it must not be a big concern. A way around this is to also include an extra gauge, the MGL TC-1, which would give you an extra four temperature monitoring channels. What do you think...am I being overly concerned about getting all four EGTs and CHTs?

[MichaelFarley56]

Good question Darick. There are a lot of people who are very happy with monitoring the back 2 cylinders only on their AeroVee. In most, if not all engines, the back 2 cylinders are the hottest ones so this makes sense.

I always think about all of the thousands of Cessna 150's and 172's out there that have no CHT monitoring and maybe one crappy little EGT gauge that never seemed to work anyway. So to answer your question, I would start by saying that the MGL Velocity is more than you really need.

That being said, with as cheap as monitors are anymore, if it were me I would probably splurge for the TC-1 so you can monitor everything. Technology is so inexpensive anymore that it makes sense to keep a close eye on your engine. Troubleshooting problems is a lot easier, and there's certainly peace of mind to be able to monitor everything.

I know this doesn't help much, but I don't think you'll be going wrong either way!

[Darick]

Thanks Mike, I know I'll feel more confident with the extra cylinder monitoring.

[Gunther]

Hello Darick. I've been wondering about what to do with cht/egt monitoring as well. Have you considered the MGL Extreme or Discovery-Lite? The RDAC (remote data acquisition computer) should greatly help with troubleshooting since you can isolate each channel at the RDAC. I'm also wondering where to place the RDAC because it might be a bit warm with the turbo.

Gunther

[Darick]

Gunther, yes I did briefly consider the Extreme but in keeping with the reality check philosophy (i.e. my budget) I decided to stay with the Sonex Velocity and Flight-2 package that is just over $1000.

[SonexN76ET]

I have the MGL Velocity engine monitor and have the probes on only the back two cylinders. I am very happy with the product. It is light, accurate, and does not require an RDAC. It was straightforward to install and configure. It is an excellent value.

[fastj22]

Could you wire some sort of switch (DPDT) to monitor all four? The switch would basically choose which thermocouples are connected to the instrument.

One way it monitors front cylinders, switch it the other way and it monitors the back ones.

[Bruce593SX]

This is what I've been thinking of doing on my aerovee, any reason it would not work?

I'm going to start my wiring soon, and have the switches already,

[fastj22]

I'm looking (very down range) at some solution to monitor 7 CTHs and EGTs for the Rotec Radial I'm dreaming of putting on my Pietenpol. The most thermocouples I've seen is 6 on any instrument.
I figure you can monitor all on a simple switch which powers a few DPDT relays and use a common switch to energize the relays.

[Sonex1517]

I believe a simpler solution would be a rotary switch. If you search online I bet you can find a solution that does not involve relays etc.

If you put that radial on a Piet I for one can't wait to see it! (In my wild dreams I imagine finding a way to put one on a Sonex....there is an RV with one that looks like a P-47)


Robbie Culver
Sonex 1517
Chicagoland
Tails and Wings complete - finishing fuselage.
N1517S reserved