PASCO ES-9070 COULOMB BALANCE - Manual (Page 17)

012-03760E Coulomb Balance
13
To replace the torsion wire, follow the numbered steps
in Figure 9. When you're done, follow the instructions
in the Setup section of this manual to balance the pen-
dulum and to zero the torsion balance.
ä IMPORTANT—When Replacing the
Wire:
➀ Begin with a length of wire at least 50 cm
long (if you've done this before, you may not
need such a long piece).
➁ Be careful not to kink the wire.
➂ As you thread the wire, the end may become
bent or kinked. It will help to clip the end off
so it remains straight.
➃ Tighten the screws that hold the torsion wire
gently. Overtightening will break the wire.
➄ The tension on the torsion wire is not a
critical variable, as long as the wire is
reasonably taut. The advantage of the spring
balance is that it helps you adjust the tension,
without pulling too hard and breaking the
wire. If you don't have a spring balance, you
can adjust the tension by feel. Just take care
not to break the wire.
Replacing the Torsion Wire