Ametek Dycor Dymaxion Mass Spectrometer, User Manual

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3-10 | Dycor Dymaxion Mass Spectrometer
RS-485 communication cables
2-Wire Mode
• Two-wire mode is recommended only when adding
a Dymaxion to an existing 2-wire QuadLink network
(Figure 3-10).
• Belden 9841 is the recommended cable. It is a
shielded cable with a single twisted pair.
• Maximum network length from the PC (or other host)
to the last Dymaxion is 4000 feet.
• Network must be configured in daisy-chain fashion.
• Star or stub lines are not recommended.
• Ground connection is recommended, but optional.
• If excessive communication errors are experienced,
try removing the ground connection.
Figure 3-10.
2-wire mode RS-485
communication cable
connections.
Two-Wire Mode
Dymaxion DB-9M
Pin 3 Ground
Pin 4 Transmit/R
Pin 5 Transmit/Receive -
PC DB-9M
Pin 3 Ground (optional)
Pin 4 Transmit/Receive +
Pin 5 Transmit/Receive -
4-Wire Mode
• Four-wire mode is recommended for Dymaxion com-
munications (Figure 3-11).
• Belden 9842 is the recommended cable. It is a
shielded cable with two twisted pairs.
• Maximum network length from the host computer to
the last Dymaxion is 4000 feet.
• Network must be configured in daisy-chain fashion.
• Star or stub lines are not recommended.
• Ground connection is recommended, but optional.
• If excessive communication errors are experienced,
try removing the ground connection
Four-Wire Mode
1st Dymaxion DB-9M
Pin 3 Ground
Pin 4 Tr
Pin 5 Transmit -
Pin 8 Receive +
Pin 9 Receive -
PC DB-9M
Pin 3 Ground (optional)
Pin 8 Receive +
Pin 9 Receive -
Pin 4 Transmit +
Pin 5 Transmit -
2nd, 3rd, etc., Dymaxion
Pin 3 Ground
Pin 4 Tr
Pin 5 Transmit -
Pin 8 Receive +
Pin 9 Receive -
Figure 3-11.
4-wire mode RS-485 communication cable connections.