Chapter 1 quick start, 4 system connections – SIGMA SQM-160 User Manual
Page 9

Chapter 1
Quick Start
1-4
1.4 System Connections
The diagram and table below identifies typical vacuum system components and their
function.
System Components
Sensor
Holds the quartz crystal used to measure rate and thickness.
Crystals must be replaced occasionally.
In-Vac Cable
A coax cable, typically 30” long, that connects the sensor to the
feedthrough.
Feedthrough
Provides isolation between vacuum and atmosphere for
electrical and cooling lines.
6” BNC Cable
Provides a flexible connection from the feedthrough to the
oscillator. Keep this cable as short as possible.
Oscillator
Contains the electronics to operate the quartz crystal. Total
cable length to the crystal should be under 40”.
10’ BNC Cable
Connects the oscillator to the SQM-160. Lengths up to 100’
are acceptable.
Ground Wire
A wire, typically braided, that connects the vacuum system to
the SQM160 ground terminal.
S e n s o r
F e e d t h r o u g h
I n - V a c
C a b l e
6 " B N C C a b l e
O s c i l l a t o r
1 0 ' B N C C a b l e
S o u r c e
S h u t t e r
G r o u n d W i r e
Fuse 1/2 A SB at 120VAC
Fuse 1/4 A SB at 240VAC
L i n e F u s e
Manufactured By
Σ
Model No. SQM-160
Ser No. 80901
instruments
S i g m a
S e n s o r 1
S e n s o r 2
R S - 2 3 2
O p t i o n A C a r d
R e l a y I / O
O p t i o n B C a r d
220
110
1
0
G r o u n d