Visit you local bicycle shop.  I'm sure they'll be able to supply miniature front and rear lED lights off the peg (as worn by cyclists - not the bike.

A method of "braking" a motor is to attach a DC motor (to act as a generator) to the shaft.  Then you can electrically load the generator to produce whatever braking force you require.  It's simple and it works !

What typical value of current are you interested in.  If several amps then a hall sensor with a 0-5volt output is your best bet.

KF2QD

Your circuit details what I explained with the exception that you have illustrated NO (Normally Open)contacts which means neither relay will ever operate.  The contacts should be NC (Normally Closed).    ie    ----[/]-----


Edit :   Just pipped to the post by abrookfield !!

Or, if it's a stuck-on relay that you want to cover against then use one of the relay NC contacts to open the feed circuit to the other relay.  Do this for both relays, then it matters not whether logic is screwed or working, it is impossible for both relays to be "energised" at the same time.  This assumes of course that the relay contacts are 100% reliable.

You are now getting an insight into how difficult it is to design a logic control system that is 100% reliable (it's impossible)

If you managed to "simply" reverse the stator (mechanically) then I suggest you have a shaded pole motor, the direction of rotation being influenced by the "side" that the shaded pole is on, with respect to the rotor core.  A photograph of the motor would end 99% of the speculation since your original question mentioned an "AC common motor", whatever one of those.

According to my son-in-law's father "you move the switch slowly"   
So much for his knowledge of electrickery

This site explains the three types of regulator far better than I can
http://www.radio-electronics.com/info/power-management/linear-power-supply-psu/shunt-voltage-regulator-theory-circuit.php

Little more information required.
a) is there a gearbox involved or are you looking directly at stepper shaft
b) how must does it move by (part of 1 step or 1 complete step)
c) do you keep the coils energised when stopped
d) if answer to (c) is "yes" are the coils really energised
e) if the answer to (c) is "no" is there a possibility of at least one of the coils being energised
f) how many coils are used
g) and finally the model number of the stepper motor

Use a hall sensor, sample current at intervals over a fixed period of time, say a couple of seconds, and add up the respective values. Then divide the totalised current by the number of samples take.  The resultant figure is the "average" current.

Basically the answer is (or should be) YES since a thermocouple is simply two different metals welded together.  There will be heat resistant insulation which may get soggy but it'll dry out once back into fresh air.

Welcome to the world of cheap-and-nasty.
Something like this might better suit but there are even better ones out there.  Simply google 5-pin din plugs and a few variants will turn up
http://cpc.farnell.com/_/av19217/din-plug-midi-5p-metal/dp/AV19217?in_merch=Products%20From%20This%20Range

One method would be to feed your input point as an analogue-in then each switch is across a different value of resistor in a divider chain.  Since this will produce a differing input as the respective resistor is shortened, the A-In will read a differing voltage and be able to determine which switch is operated.  Note that this system only caters for one switch being operated at any time.  If you google R-2R you'll get info on how this is accomplished

Or if you want something really simple just use one of your 15 volt supplies.  Connect to it an isolated switch mode converter that outputs 15 volts and connect it's output such that the inverter positive output is connected to the original supply negative.  This then gives you the +/- 15 volt supply you desire.

It's actually amazingly simply to create sound from electrical "voltage" oscillations.  As a youngster I "discovered" that by using a neon type screwdriver with the 'live" end stuck into a 240v live socket, and the "finger" end place into the ear using a steel knitting needle as a bridge-piece, one could actually hear the 50hz hum.  Of course that was in the days when you were able to experiment without the safety elves ensuring that we all ended up frightened to live. I lived to tell the tale.