What's on your TCW IBBS Backup Battery?

[Carl Froehlich]

Ed,

PM me your email address and I?ll provide details on the dual battery install. It is flying on four RVs over the last decade and has proven itself.

Carl

[supik]

Originally Posted by Carl Froehlich

Ed,

PM me your email address and I?ll provide details on the dual battery install. It is flying on four RVs over the last decade and has proven itself.

Carl

Carl,

Can you make your diagram public here for others as well?

[Carl Froehlich]

Originally Posted by supik

Carl,

Can you make your diagram public here for others as well?

I would, but too many pages to upload.

Happy to send to anyone who PMs me their email address.

Carl

[Tag]

Hello Carl,

I?m very interested in your system. I?m still at the the ?canoe? stage, but starting to think ?bout the wiring, among other things.... Thanks

Charlie

[MarkW]

Originally Posted by snoop9erdog

Thx Mark. Love your 9.

Have you been satisfied with the TCW battery? It senses main battery voltage and then kicks on, correct?

Do you do as the manual says....power up everything first and leave ON?

Hey Ed,
Sorry for the late reply. I like the TCW system and would do it again.
I have not checked the capacity with a load test in a while but this thread has reminded me to do that.
I wired per the manual with a toggle switch that is left on during all ops.
I also use an E-buss through a diode.

[snoop9erdog]

Originally Posted by Walt

Having the GTN on there is interesting and presents a pretty heavy load on the TCW, when transmitting the unit may draw more than the 4 amps listed (10 amp breaker on the com side and 7.5 on the nav side) and generally uses 18ga wire to support that current flow. The feed thru CB on the TCW is shown as 10amp to carry everything?

Personally... I use the back-up battery for PFD, ADAHRS, GEA24 only.
If you really want a GTN or com on a backup I would use a separate TCW for this or larger backup source.

Walt,
Should one put the GMU 11 on the IBBS as well or would that be unnecessary?

[MacCool]

They shipped me a TCW IBBS 3 AH as backup with my new AFS 5400. I have elected instead to use my second Pc680 as backup in case of alternator failure. If my alternator dies...I'll just flip the second master switch and bring that backup battery online. 16 AH instead of 3 AH backup. Not sure I see a need for the IBBS.

[avrojockey]

I have the 3ah TCW IBBS, in an IFR panel I fly IFR regularly. This is what I have...

1. GDU 370
2. GDU 375
3. #1 GSU 25
4. GEA 24
5. GPS 175
6. GMC 307 (no AP servos but to control FD, draws only mA)
7. GAD 29
8. GTX 335

Total draw is calculated just under 5A, but tests show a little less as the 3ah IBBS lasted 59 min.

I went back and forth over a couple things:
1. COM...big variable draw. Decide this is an emergency I can squawk 7700 and use my backup handheld if needed.
2. GMC 307...not needed but a nice item during stressful situation, and it draws like 180mA
3. Both GDUs...there wasn't a need but I wanted the brown-out capability during start.
4. Decided against the GSU 25 #2 because of the additional load and the GPS 175 has an AHRS feeding ForeFlight if 10^-9 rears it's ugly head

I opted for the IBBS over a second battery because of weight. The IBBS is an emergency...I have and hour to get in the ground...plenty of time in the lower 48. Of course, the way my system is designed, things would need to be pretty bad to get down to just the IBBS. Alternator and battery failure, or a significant short prompting isolating both the main and endurance buses. If you use my IBBS test to gauge my healthy battery life, I would guess my battery would last about 2 hrs longer than my fuel endurance. Thats why I didn't think there was a need for another heavy battery.

[Walt]

Originally Posted by snoop9erdog

Walt,
Should one put the GMU 11 on the IBBS as well or would that be unnecessary?

Either way, the GMU11 current draw is minimal.

[Andrew Anunson]

Originally Posted by avrojockey

I have the 3ah TCW IBBS, in an IFR panel I fly IFR regularly. This is what I have...

1. GDU 370
2. GDU 375
3. #1 GSU 25
4. GEA 24
5. GPS 175
6. GMC 307 (no AP servos but to control FD, draws only mA)
7. GAD 29
8. GTX 335

Not arguing against your lineup at all... just curious as to why you want to have a transponder in an emergency instead of your COM. I am currently installing my IBBS and need to make some decisions and appreciate your help. I don't want to revert to my handheld COM during an emergency. The GTX shouldn't be required if we're down to the IBBS.... does the GTX make a big difference if we need ATC help to get back on the ground?