Adding EGT Probes

[ZK-SVH]

Hi there everyone.

I‘m installing Skyview HDX system on a Rotax 912 ULS. I have the EMS220 and the Rotax kit. The kit contains wiring and two probes.

If I want to install probes on the other two cylinders should I just buy two more probes and wire them to the appropriate pins on the plug? And for the wire extension should I get EGT extension wire? Is Type K thermocouple wire for directly connecting to EGT probes?

Thanks Peter

 

[Stevec]

Hi Peter

check out the installation manual on page 7-43 and 7-45 it describes what is acceptable for extending the EGT sand CHT wires.

 

[Dynon]

Yep, type K thermocouple to extend ; don't have a junction across a temperature change (ie firewall).

 

[SV_Classic]

Yep, type K thermocouple to extend ; don't have a junction across a temperature change (ie firewall).

Can the wires on a stock CHT or EGT probe be shortened? I found this in the manual, "It is recommended to not cut the “armored” portion of the cable near the sensor end of the CHT or EGT sensors." but does this mean that they can't be shortened at all or to just not cut them so short that you get close to the sensor ends?

Also, it appears the builder of my plane used the brown extension wire for both the CHT and EGT sensors. Is this ok or is there a different extension wire for the CHT sensors?

Lastly (3rd edit ), what are the best connectors to use for sensor extensions forward of the firewall where there is likely to be a lot of oil residue.

Thanks!

 

[SV_Classic]

Response from Dyson Support via email was, try not to cut the braided lengths of sensor wire, their harnesses use the brown wire for CHT and EGT, any high quality connector is fine

 

[swatson999]

Also, it appears the builder of my plane used the brown extension wire for both the CHT and EGT sensors. Is this ok or is there a different extension wire for the CHT sensors?

No, it is not OK to just "use the brown wire". You have to use the correct brown wire for the sensor type. CHT uses J-type thermocouple wire (white and red pair), EGT uses K-type thermocouple wire (yellow and red pair).

This is in the installation manual.

Dynon Avionics sells both J and K type thermocouple wire which may be used to connect the desired thermocouple to the SkyView. Ensure you order the correct wire type for the thermocouple you intend to use. Crimp a Female DSUB pin on the end of each wire, and plug them into the SV-EMS-220’s EMS 37-pin Main Sensor Harness D37. Polarity is important, so ensure that you are routing the positive side (yellow for K-type; white for J-type) of the thermocouple to pin 27 or pin 36 on the 37-pin harness, and the negative side to pin 28 or pin 37.

 

[SV_Classic]

The harness sold by Dynon, and confirmed by Dynon tech support, uses the brown wire for both types of sensors. I was surprised to learn this but if they vouch for it then I'll give it a try before I worry about it.

 

[n144sh]

The harness sold by Dynon, and confirmed by Dynon tech support, uses the brown wire for both types of sensors. I was surprised to learn this but if they vouch for it then I'll give it a try before I worry about it.

the brown is just the jacket. K type (EGT) are red/yellow, J type (CHT) are red/white.

 

[SV_Classic]

That makes sense, thanks for clarifying.

 

[swatson999]

I thought I just said that.

 

[SV_Classic]

When you shop for sensor extension wire, there is the brown type K thermocouple extension wire compatible with a Dynon EGT sensor and there are wires for other sensors that don't appear to come in a brown insulator. Maybe they do but the photos don't show it that way. It appeared to me that the brown wires in the Dynon harness were all the same which was the basis of my question. What I didn't get from your reply was that inside the brown insulation were two different types of wires, white/red (CHT) and yellow/red (EGT). If that was what you were trying to explain, I didn't catch it.

 

[swatson999]

This is all available in the installation manual, plus you should open up the cowling and *look at the wires*. This would probably have shown you immediately, sans the delay of posting/replies/more posting/more replies, that the "brown" wires are really brown coverings over two differently colored sets of pairs of wires (yellow and red, white and red). Which a quick search of the manual would have found the description of the difference. Looking at the pinouts in the manual would have shown the same. Pulling the connector from the EMS and opening the backshell would have, likewise, shown you that the "brown" wire is actually a pair of thermocouple wires.

If you're going to maintain this aircraft, you're going to have to learn to do considerable research and learning. Might I suggest starting by reading, *cover to cover*, all of the installation and user's manuals for all devices and avionics.

 

[Guenin]

Good Lord. I've never encountered a bigger collection of scolds.

 

[SV_Classic]

Some people have to let everyone know how big they are. He has no idea who I am or what my eperience level is. I asked a simple question in preparation for work I have to do to the plane I bought after having already completed a lot of other stuff. And it is just bad social media behavior, it certainly doesn't help Dynon to sell hardware when their community thinks "read the manual" is a universally acceptable reply to a lot of simple questions for new customers or potentially new customers. So many opportunities to welcome and encourage people here are lost to "read the manual" replies.

 

[swatson999]

Do you know how many times someone's first post here is "How do I do _____?" without having even *tried* to look up the answer in the manuals? You were told several times about the different types of thermocouple wire, AND it's in the manual.

We're all for helping others out here, but I think we expect people to at least have read the manuals thoroughly, examined the parts themselves, and tried to sort it out before just asking someone to fix it for them.

 

[SV_Classic]

As someone who currently hosts a friendly aviation themed forums site and who formerly hosted for-profit forums sites, I know that new members sometimes get ahead of themselves and ask questions that others find too basic or repetitive and therefore annoying. These posts help new members to break into the community though and it is through the supportive replies of other members that they feel welcome and often go on to be the ones that help the next generation of new arrivals. It isn't annoying, it's how online communities grow new wood and stay healthy.

You didn't quite understand my question and instead of asking for clarification you answered it the way you saw fit and are now annoyed that I didn't get what I needed from your answer. Boorish was the word I used to describe your reply in the post that I deleted from this thread.

I don't see you having an epiphany about this, I've dealt with a lot of people like you and they don't usually stick around a well moderated site because they don't get to call the shots and scare away new members. Like I said, you're not doing Dynon any favors with your attitude unless they like people not buying their equipment. Fortunately for me, Dynon tech support via email has been exceptionally helpful and my project has been moving along very nicely.

 

[swatson999]

I understood exactly what your question was and answered it precisely in Post number 6.

 

[swatson999]

And just to quote from the Forum Posting Rules:

• Folks are almost happy to help with installation questions. But before asking a question, please search the Installation Manual or Pilot User Guides that are available at http://docs.dynonavionics.com. These PDFs can be searched: CTRL+F (PC) and Command+F (Mac) are your friends.
• If you can't find the information you're looking for in our manuals, please search these forums next! There are literally tens of thousands of threads on here. Most questions have been answered more than once already.

 

[SV_Classic]

smh, you don't get it, I quoted the manual in my post, obviously I had already been reading the relevant sections of the manual but didn't get what I needed from them. Please get over yourself.

 

[swatson999]

smh, you don't get it, I quoted the manual in my post, obviously I had already been reading the relevant sections of the manual but didn't get what I needed from them. Please get over yourself.