I don't know if this is standard practice, but when I use the Schurter
110/220 switch, I wire it for contact redundancy by wiring pins 2 and 3
together for one side of the switch and pins 1 and 4 together for the other
side. When the switch is turned on, 1 connects to 2 and 3 connects to 4
making a redundant SPST switch. Never had one fail.
_____
From: roc-chat-bounce@xxxxxxxxxxxxx [mailto:roc-chat-bounce@xxxxxxxxxxxxx]
On Behalf Of Kurt Gugisberg
Sent: Thursday, January 12, 2017 9:13 AM
To: roc-chat@xxxxxxxxxxxxx
Cc: James Dougherty; Mike Kramer
Subject: [roc-chat] Re: Switch Warning with StratoLogger CF
I have used those rotary switches for years. I haven't had one split apart
on me and I'm not sure if I have had any failures either, although I had one
in the ill fated Nibbles flight last year with it's total electronic
failure. So it could have failed. I also use screw switches alot, the
Featherweight switch as well as the Aerocon screw switch. They are, more or
less, foolproof.
Also, three hundred operating cycles would be a lot in rocketry.
Kurt
On Thu, Jan 12, 2017 at 8:13 AM, R Dierking <applerocketry@xxxxxxxxxxx>
wrote:
Hum, that doesn't sound good. I'll have to take a look at what Mike has
designed. It would be nice if a retrofit would fit inside the existing hole
used for the 110/220 switch. Or, perhaps remove the guts from the 110/220
and replace it with something more durable/reliable.
From: James <mailto:jafrado@xxxxxxxxx> Dougherty
Sent: Thursday, January 12, 2017 8:09 AM
To: roc-chat@xxxxxxxxxxxxx
Cc: Mike Kramer <mailto:kramer@xxxxxxxxxxxx>
Subject: [roc-chat] Re: Switch Warning with StratoLogger CF
They split in half!!
Ive also seen people turn them and they split in half.
Its designed for a wall socket!
Yes, do what Mike said - great plan; Never seen that fail ...
Sent from my iPhone
On Jan 12, 2017, at 7:22 AM, R Dierking <applerocketry@xxxxxxxxxxx> wrote:
Yes, I would like to try this out Mike, please send the file. I'll look
into the materials available for the printer. I think I only have PLA at
the moment. How about ABS?
From: Mike <mailto:kramer@xxxxxxxxxxxx> Kramer
Sent: Thursday, January 12, 2017 7:09 AM
To: ROC <mailto:roc-chat@xxxxxxxxxxxxx> Chat
Cc: ROC Chat <mailto:roc-chat@xxxxxxxxxxxxx> ; James Dougherty
<mailto:jafrado@xxxxxxxxx>
Subject: [roc-chat] Re: Switch Warning with StratoLogger CF
richard,
I use micro switches with a screw to arm them. Uses a small hole in the side
of the rocket and makes it highly unlikely that the electronics can be in
advertently armed.
Easy to 3d print the mount for it. I will send you a file tonight.
Side note, don't use PLA ( unless it is the pro spec kind) for parts, it
can't survive the temperatures on the lake bed. I'm using PETG or Nylon.
Mike K
On Jan 12, 2017, at 6:47 AM, R Dierking <applerocketry@xxxxxxxxxxx> wrote:
I just purchased a PerfectFlite StratoLoggerCF altimeter and the
documentation came with a Switch Warning about failures of the 110/220
rotary switch that some people have been using for powering electronics.
High resistance and intermittent connection are noted in the document.
The document says "numerous reports" of failures, but I'm curious if this is
a problem with a group/lot of these switches or a pervasive problem to this
particular switch or rotary-type switches in general when used for rocketry.
I've used these switches in the past and tested the 4 I'm currently using on
two projects. I'm not detecting any problems with these switches.
Please keep in mind that there are several variations for this make of
switches. Here's some info on what I have:
Schurter, Voltage Selector Switch, 2 Stages, Series-Parallel, SWA1 or SWA2
Also, it's interesting that the spec sheet says that the lifetime is 300
operating cycles (without load).
So, does anyone have a personal experience that was bad with these switches?
Also, I think many people would be interested in recommendations on arming
switches both commercial and custom.
Thank you,
Richard Dierking
