Rice Lake 920i Dual Channel A/D Card - Manual (Page 2)

2 920i Dual Channel A/D Card Installation Instructions
8. If using 6-wire load cell cable (with sense
wires), remove jumpers JP1 and JP2 before
r e i n s t a l l i n g c o n n e c t o r J 1 . F o r 4 - w i r e
connections, leave jumpers JP1 and JP2 on.
Remove jumpers JP3 and JP4 for 6-wire
connections to J2.
9. When connections are complete, reinstall load
cell connectors on the A/D card and use cable
ties to secure the load cell cables to the inside
of the enclosure.
10. Position the backplate over the enclosure and
reinstall the backplate screws. Use the torque
pattern shown in Figure 3 to prevent distorting
the backplate gasket. Torque screws to 15 in-lb
(1.7 N-m).
1
3
5
14
17
16 12
9
8
7
10
11
18
15
4
2
6
13
Torque backplate screws
to 15 in-lb (1.7 N-m)
Figure 3. 920i Enclosure Backplate
11. Ensure no excess cable is left inside the
enclosure and tighten cord grips.
12. Reconnect power to the indicator.
13. The
920i
automatically recognizes all installed
option cards when the unit is powered on. No
hardware-specific configuration is required to
identify the newly-installed card to the system.
Calibrate the A/D card using the procedures
described in the
920i
Installation Manual, PN
67887.
Specifications
Excitation Voltage 10 ± 0.5 VDC,
16 x 350¾ or 32 x 700
 load
cells per A/D card
Sense Amplifier Differential amplifier with
4- and 6-wire sensing
Analog Signal Input Range –10 mV/V to +70 mV/V
Analog Signal Sensitivity 0.3 uV/grad minimum @ 7.5 Hz
1.0 uV/grad typical @ 120 Hz
4.0 uV/grad typical @ 960 Hz
A/D Sample Rate 7.5–960 Hz, software selectable
Input Impedance >35 M¾ typical
Internal Resolution 8 000 000 counts
Wt Display Resolution 9,999,999
Input Sensitivity 10 nV per internal count
System Linearity ±0.01% of full scale
Zero Stability ±150 nV/°C, maximum
Span Stability ± 3.5 ppm/°C, maximum
Input Voltage Differential ±800 mV referenced to earth
ground
Input Overload Load cell signal lines ±10 V
continuous, ESD protected
RFI/EMI Protection Signal, excitation, and sense
lines protected