Schleicher Power/Solar rotary switch specs?

[noel.wade]

Hello,

Anyone out there have specs/measurements for the rotary switch that Schleicher installs in their newer gliders, to enable switching between batteries?
(see the lower-left part of the panel in this image, as an example: Loading Image... )

Thanks!

--Noel

[John Carlyle]

I took a switch like that out of a friend's ASW-27. The 6-position switch is made by Marquardt, is model 9030.01 and is labeled 4A 30V DC.

-John, Q3

Post by noel.wade
Hello,
Anyone out there have specs/measurements for the rotary switch that Schleicher installs in their newer gliders, to enable switching between batteries?
(see the lower-left part of the panel in this image, as an example: http://cdn-www.airliners.net/aviation-photos/photos/9/2/2/1272229.jpg )
Thanks!
--Noel

[noel.wade]

Thanks, John!

--Noel

[b***@gmail.com]

Post by John Carlyle
I took a switch like that out of a friend's ASW-27. The 6-position switch is made by Marquardt, is model 9030.01 and is labeled 4A 30V DC.
-John, Q3

I have yet to find this rotary switch available from a US electronics house like Mouser or DigiKey. If you do find it from an US house, please provide details.

Like rotary switches are available in the EU but by the time and expense you could buy one from Murray at Eastern Sailplane for about the same cost.

For what it's worth, checking the current Marquardt catalog, the only rotary switch currently offered are 3 model number 1703.XXXX somethings.

[noel.wade]

Yup. I've reached out to Marquardt USA; will post here with into if they get back to me.

I am not after a direct replacement, though... I'm trying to find a make-before-break (or "shorting") switch that fits with minimal changes to the panel or labeling. It's annoying to lose voltage and have avionics reset when switching from one batt to the next! :-P

--Noel

[John Carlyle]

That's exactly why my friend wanted me to change his switch. I put in 2 SPST toggle switches for him - end of problem with rebooting instruments upon switching batteries.

There are make-before-break rotary switches. I've put a a few Cole-Hersee 72171-01 switches for friends. They handle 20A at 12V DC.

-John, Q3

Post by noel.wade
Yup. I've reached out to Marquardt USA; will post here with into if they get back to me.
I am not after a direct replacement, though... I'm trying to find a make-before-break (or "shorting") switch that fits with minimal changes to the panel or labeling. It's annoying to lose voltage and have avionics reset when switching from one batt to the next! :-P
--Noel

[b***@gmail.com]

Post by John Carlyle
That's exactly why my friend wanted me to change his switch. I put in 2 SPST toggle switches for him - end of problem with rebooting instruments upon switching batteries.
There are make-before-break rotary switches. I've put a a few Cole-Hersee 72171-01 switches for friends. They handle 20A at 12V DC.
-John, Q3

Post by noel.wade
Yup. I've reached out to Marquardt USA; will post here with into if they get back to me.
I am not after a direct replacement, though... I'm trying to find a make-before-break (or "shorting") switch that fits with minimal changes to the panel or labeling. It's annoying to lose voltage and have avionics reset when switching from one batt to the next! :-P
--Noel

This Cole-Hersee switch looks perfect and is reasomably priced. How do you know it is a "make contact before break contact" switch?

http://www.partdeal.com/cole-hersee-sp4t-heavy-duty-20-amp-rotary-switch-12-volt-72170-04.html

[John Carlyle]

Go to this site: http://www.elecdirect.com/product/f2fab26c-e2db-451c-8a9d-f333feeb9107.aspx Click on the PDF logo under See specs. On the right hand side at the top of the 3rd page of the resulting PDF you'll see "Heavy Duty 20A 12V Part numbers refer to the switch complete with knob. Without illumination. In the diagrams 'On + - 1, + - 2' indicates a + terminal connected to terminals 1 and 2. These switches are make before break."

-John, Q3

Post by b***@gmail.com

Post by John Carlyle
That's exactly why my friend wanted me to change his switch. I put in 2 SPST toggle switches for him - end of problem with rebooting instruments upon switching batteries.
There are make-before-break rotary switches. I've put a a few Cole-Hersee 72171-01 switches for friends. They handle 20A at 12V DC.
-John, Q3

This Cole-Hersee switch looks perfect and is reasomably priced. How do you know it is a "make contact before break contact" switch?

[Steve Koerner]

I think there's a better way to address the problem... Each item on your panel has an associated double pole, center off power switch. So every item can be individually connected to one battery or the other. When you are powering up your panel, you assigned batteries to the various gadgets in a way that pretty much balances the load.

This approach means that there isn't any switching batteries in flight. You never need to think about it. It also means that you don't have to deal with the question of how low should I draw battery 1 down before switching to battery 2. For all battery types it's better to not be drawing them down deeply if you want to maximize their life; splitting the load evenly is thus better for overall battery life. And, of course, you preclude this problem of switching transient.

[noel.wade]

All -

Appreciate the suggestions and yes a bank of toggle switches would work; but would require me to monkey with the panel and the wiring, which I'm trying to avoid (its flying season!) :-)

Steve - That works and _does_ provide several benefits. But you either need to divide the load relatively evenly between your batteries, or do maths and ensure the Ah of your batteries matches the relative draw of each circuit (but then you have to remember which batteries to install where, in your glider).

The Cole-Hersee line is a bit bulky and doesn't appear to match the 6-position, 60-degree switch function of the Marquardt unit (which is OK from a functional standpoint, but means re-labelling the panel). I'll keep it in mind; but the hunt continues... :-)

--Noel

[m***@hotmail.com]

With the new lifepo batteries offering a higher nominal voltage, the solution of wiring all your avionic batteries in parallel with a high capacity low voltage drop schottky diodes in line with each batt makes a lot of sense. You will always be pulling from the best batterie(s) and you never have to do any switching....ever. You can find 18A diodes which have only a 0.4V forward drop at digikey. I've done this for over 10 years with lead acid batts and never had an issue even on long flights with a transponder running.

[noel.wade]

Post by m***@hotmail.com
wiring all your avionic batteries in parallel with a high capacity low voltage
drop schottky diodes in line with each batt makes a lot of sense.

Sure, that makes some sense and I could see doing that with many gliders. For those of us with a solar panel/charging system, though, the Schottky diodes are a problem. :-P I guess the thing to do would be to splice in the charging wires between each battery and its Schottky, eh?

--Noel

[JS]

But you probably would prefer to charge only the battery (or batteries) you used, not all of them?
The multi-position rotary switch is nice. If you need to add another battery, no new switches are required.
Jim

[noel.wade]

Post by JS
But you probably would prefer to charge only the battery (or batteries) you used, not all of them?
The multi-position rotary switch is nice. If you need to add another battery, no new switches are required.
Jim

Jim - I'd preserve the multi-position rotary switch that controls which battery the solar system is charging. AFAIK, that switch just ties into the supply wires for the "main" power switch (the one that he's suggesting I get rid of entirely). I'm a neophyte when it comes to electronics that aren't measured in bits and bytes; but I think that as long as the Schottky diodes are "downstream" of the charging wires, I should be OK.

What I'm not convinced of, is whether having all of the batteries ganged together in parallel could result in a charge imbalance (similar to when individual cells in a battery-pack wind up with imbalanced states of charge - although those are typically wired in series, not in parallel).

[JS]

Sorry, Noel. I meant charging after flight. Why pull all the batteries out of the glider to top up when you only needed to use one?
For example yesterday the full panel (TXP, COM, VGA, FLARM and 2 varios) was on for only 4.5 hours so just one battery needed charging.
Jim

[a***@gmail.com]

Post by noel.wade
All -
Appreciate the suggestions and yes a bank of toggle switches would work; but would require me to monkey with the panel and the wiring, which I'm trying to avoid (its flying season!) :-)
Steve - That works and _does_ provide several benefits. But you either need to divide the load relatively evenly between your batteries, or do maths and ensure the Ah of your batteries matches the relative draw of each circuit (but then you have to remember which batteries to install where, in your glider).
The Cole-Hersee line is a bit bulky and doesn't appear to match the 6-position, 60-degree switch function of the Marquardt unit (which is OK from a functional standpoint, but means re-labelling the panel). I'll keep it in mind; but the hunt continues... :-)
--Noel

I found a near direct replacement, 4-amp, 6-position micro rotary switch that I've been using for 2 years. I looked a long time and could never find a make before break micro rotary switch. Instead I put a capacitor (several actually) and a power resistor across the circuit to keep continuity - which works well as long as the voltage isn't too low. With LiFePO4 batteries voltage drop isn't a problem. One of the positions is also battery 1+2 slaved together through a pair of power diodes so if one battery goes bad in flight it doesn't take down half my panel or the other battery (and my entire panel). Again, with LiFePO4 batteries' flat voltage curve the slight voltage drop through the power diodes isn't a problem. I never get a low battery warning now. If everything goes to hell, I saved one position on the switch for the 5 Ah SLA tail battery.

[a***@gmail.com]

Post by a***@gmail.com

Post by noel.wade
All -
Appreciate the suggestions and yes a bank of toggle switches would work; but would require me to monkey with the panel and the wiring, which I'm trying to avoid (its flying season!) :-)
Steve - That works and _does_ provide several benefits. But you either need to divide the load relatively evenly between your batteries, or do maths and ensure the Ah of your batteries matches the relative draw of each circuit (but then you have to remember which batteries to install where, in your glider).
The Cole-Hersee line is a bit bulky and doesn't appear to match the 6-position, 60-degree switch function of the Marquardt unit (which is OK from a functional standpoint, but means re-labelling the panel). I'll keep it in mind; but the hunt continues... :-)
--Noel

I found a near direct replacement, 4-amp, 6-position micro rotary switch that I've been using for 2 years. I looked a long time and could never find a make before break micro rotary switch. Instead I put a capacitor (several actually) and a power resistor across the circuit to keep continuity - which works well as long as the voltage isn't too low. With LiFePO4 batteries voltage drop isn't a problem. One of the positions is also battery 1+2 slaved together through a pair of power diodes so if one battery goes bad in flight it doesn't take down half my panel or the other battery (and my entire panel). Again, with LiFePO4 batteries' flat voltage curve the slight voltage drop through the power diodes isn't a problem. I never get a low battery warning now. If everything goes to hell, I saved one position on the switch for the 5 Ah SLA tail battery.

http://www.mouser.com/ProductDetail/NKK-Switches/MRY106-A/?qs=sGAEpiMZZMvNbjZ2WlReYkTkcZZOLKFnRt9TIA5Tpms%3d

[Ian]

Post by Steve Koerner
I think there's a better way to address the problem... Each item on
your panel has an associated double pole, center off power switch.
So every item can be individually connected to one battery or the
other. When you are powering up your panel, you assigned batteries
to the various gadgets in a way that pretty much balances the load.

I have this in my panel. But instead of a whole row of switches I just
have two. The instruments are in two groups, one group on each switch.
Each group can be powered of on or the other battery or isolated completely.

Still if I need to switch the FLARM/Vario between batteries I loose my
GPS fix and final glide calcs in the vario. Not too cool.

I have also got a pair of diodes to draw from the best battery - but
that just powers the logger and the U/C warning. I would not want this
on my transponder as I often leave it on the weakest battery with the
intention of switching it off if the battery goes flat while I reserve
the good battery for more essential equipment like the radio and final
glide computer.

There is no single easy answer to this.

Ian

[kirk.stant]

Post by Ian

Post by Steve Koerner
I think there's a better way to address the problem... Each item on
your panel has an associated double pole, center off power switch.
So every item can be individually connected to one battery or the
other. When you are powering up your panel, you assigned batteries
to the various gadgets in a way that pretty much balances the load.

I have this in my panel. But instead of a whole row of switches I just
have two. The instruments are in two groups, one group on each switch.
Each group can be powered of on or the other battery or isolated completely.

Exactly the system I've been using for the last 14 years, without problems. Even when switching one of the "busses" from a weak battery to the other one, my logger/flight computer hasn't had an issue with the momentary power loss.

Simple and easy to maintain.

Kirk
66

[John Carlyle]

If you don't mind a slightly used (but perfectly serviceable) rotary switch of this exact model, make me an offer.

-John, Q3

Post by b***@gmail.com
I have yet to find this rotary switch available from a US electronics house like Mouser or DigiKey. If you do find it from an US house, please provide details.
Like rotary switches are available in the EU but by the time and expense you could buy one from Murray at Eastern Sailplane for about the same cost.
For what it's worth, checking the current Marquardt catalog, the only rotary switch currently offered are 3 model number 1703.XXXX somethings.

[b***@gmail.com]

Post by John Carlyle
I took a switch like that out of a friend's ASW-27. The 6-position switch is made by Marquardt, is model 9030.01 and is labeled 4A 30V DC.
-John, Q3

Post by noel.wade
Hello,
Anyone out there have specs/measurements for the rotary switch that Schleicher installs in their newer gliders, to enable switching between batteries?
(see the lower-left part of the panel in this image, as an example: http://cdn-www.airliners.net/aviation-photos/photos/9/2/2/1272229.jpg )
Thanks!
--Noel

Switch available from Bürklin GmbH & Co. KG, Grünwalder Weg 30, 82041 Oberhaching, Germany

https://www.buerklin.com/en/catalog/Multistep-rotary-switches-series-9030-type-Marquardt-9030-9032-G357200.html

[Dan Daly]

On my SZD-55, I have an 'OLK box' that has a circuit which maintains power when you switch batteries (also indicates when voltage drops to 11.5 v with a yellow LED). My switch to LiFePO means I rarely see that led anymore (Stark from Tom Knauff's). I'd get one on my next glider (should I ever marry money or win the lotto).

Dan
2D