I’d like to use a Tech-Aero IBEC but I’d also like to use a separate ignition battery. Do you think I can separate their receiver plug and have the white wire go to the receiver channel and the red and black wire go to the ignition battery?

Use a SmartFly device that uses a dedicated ignition battery if you're not comfortable with the TechAero Ultra.

The Tech Aero is designed to run power through the Rx period. If you want a second battery, just use an open port in your Rx, or a batt-share switch like the Badger... So, no don't try to run power directly through TA device.

The TA Ultra is very reliable when used as designed.

The TA is a true IBEC that eliminates the ignition battery. There's no reason to use it if you're not wanting to eliminate the ign battery.

You just need a SmartFly optical ign switch.

<<I’d like to use a Tech-Aero IBEC but I’d also like to use a separate ignition battery.>

Why?

Originally Posted by DGrant

The TA is a true IBEC that eliminates the ignition battery. There's no reason to use it if you're not wanting to eliminate the ign battery.

You just need a SmartFly optical ign switch.

Or the RCEXL switch...
Having said that, I don’t understand why one would ever use an “ignition battery”. At most, a DA-120 draws about 500 mah.

Originally Posted by ghoffman

Or the RCEXL switch...
Having said that, I don’t understand why one would ever use an “ignition battery”. At most, a DA-120 draws about 500 mah.

There's another good ignition kill device.

...but yeah I agree there's no problem with using the TechAero IBEC and ditching the ign battery.

My 100cc planes use average of 350mah's per flight, running everything on dual HV Lipos(2800mah each) , 6 high torque servos, ignition(TechAero), timed flights of 10 minutes, ... through Spektrum PS Rx. It's slick and easy.

Twin ignition systems are approx 1A at 6000 rpm, atleast thats what I remember......

I have both RCExl and Tech Aero. I cant tell a difference in the 2 when they are in the air. Its just a visual inside the airplane, thats all. But yes, the RCExl can use a seperate battery to get its power from. We all want to make things really simple inside our airplanes, with less maintenance involved.

And to that end, I have had a RCEXL fail, never had a Tech Aero fail.

Originally Posted by Bunky F. Knuckle

Twin ignition systems are approx 1A at 6000 rpm, atleast thats what I remember......

You are probably pretty close. From CH Ignitions page, in reference to the CH/RCexl ignitions on a single cylinder at 8000rpm

• 7.2 Volts -725 mA
• 7 Volts -675 mA
• 6 Volts -650 mA

Since few of us fly WOT all the time, the average current draw during a flight is fairly low, and much less than the above.

I use the TechAero Ultra IBEC these days because it does away with the battery.

I have SmartFly system in one of my planes too(it was already in the plane)..with dedicated ignition battery. It's not an IBEC, it's an optical kill switch.

Both work as they should.

An "IBEC" is an "ignition BATTERY ELIMINATOR circuit". It eliminates the ignition battery by design.

If you use a dedicated ignition battery it's not an IBEC... Call it semantics, or whatever, but correct terminology can make a difference... and usually helps with communication and understanding.

If you want to use a separate battery look at the Powerbox Spark Switch.

Personally I use the IBEC on all my planes. I’ve been using them since Ed first brought them out like 20 years ago. I’ve never had a failure.

Originally Posted by William_Burkert

I’d like to use a Tech-Aero IBEC but I’d also like to use a separate ignition battery. Do you think I can separate their receiver plug and have the white wire go to the receiver channel and the red and black wire go to the ignition battery?

No reason why you cant do this, But i Would look a PB Sparkswitch or Sparkswitch Pro ( Gives RPM and Telemetry data) model if you wished to use a separate battery.

But if wishing to use what you have on hand then i cant see any issues.

To answer the original question, I would tie the negatives together on both batteries. The connections on the IBEC;
Signal - From receiver
Positive - From ignition battery
Negative - Receiver and ignition battery.
Normal range check.

I used the smart fly for years in all my planes. Their products are bullet proof in my opinion.

I switched to TC for the obvious reason of eliminating the batt. 3 planes for 5 years now without issue.

As was mentioned makes no sense bastardizing a TC. Besides the smart fly will save you money as well.

If the purpose of using a separate ignition battery is to address concern about possible ignition interference and ensuring adequate isolation from the receiver, then even connecting the signal line from the Tech Aero IBEC to the receiver would still present the same "risk". Buy a Smart Fly optical ignition kill and don't bastardize the TA IBEC connection.

If the purpose of using a separate ignition battery is to ensure adequate battery capacity to run the ignition, then simply use a larger receiver battery.

If the purpose of using a separate ignition battery is to provide battery redundancy, then simply run 2 receiver batteries as many of us do, with either dual switches or some other form of electronic redundancy.

Perhaps I am just an idiot today and failing to see the obvious, but there is just no rationale to use a Tech Aero IBEC connected as described.