2
Installation
Making the Back Panel Connections
14
Accela PDA Detector Hardware Manual
Thermo Scientific
Connecting the Analog Outputs
The installation kit provides two analog signal cables (twin-axial computer cables) to connect
the analog outputs from the PDA detector to other data collection devices.
The analog signal cables have three wires protruding from the ends of the shielded cable. Two
of these wires are electrically insulated and carry an analog signal to data collection devices.
Typically, the wire with the clear insulation is connected to the positive analog output, and the
wire with the black insulation is connected to the signal ground (sometimes referred to as the
negative signal). The third wire is not insulated and grounds the cable shielding. The cable
shielding reduces signal noise caused by radio frequency interference and is most effective if
the bare wire is grounded at just one end.
The ends (1/4 in.) of the analog signal wires are stripped and soldered to allow electrical
contact and to prevent fraying.
On the detector’s back panel, there are two analog output channels with three different analog
voltage outputs per channel: CHA – 10 mV, CHA – 100 mV, CHA – 1 V, CHB – 10 mV,
CHB – 100 mV, CHB – 1 V; and a single ground per channel: GND A and GND B. Select
the appropriate output voltage for your data collection system.
Y
To make each electrical connection
1. Insert the end of the wire into the appropriate terminal in the 8-pin terminal connector.
Hold the wire in place while you tighten the small terminal set screw firmly onto the wire.
2. Insert the terminal connector into the 8-pin analog connector numbered 9 through 16 at
the back of the instrument (see
Figure 10.
Analog signal connectors
IMPORTANT
Do
not
connect the detector ground terminals to any earth ground on
your data system computer. Doing so leads to an increased noise level and a
subsequent decrease in sensitivity.
1 2
34
5
678
9
0
1 2
34
5
678
9
0
Analog signal
8-pin connectors
