Cardinal 748 - Page 5

4
PIN 13
PIN 14
PIN 25
PIN 1
PRESET WEIGHT COMPARATOR LOGIC LEVEL OUTPUT
To automatically switch AC powered external devices at up to eight preset weight values, connect
the RB4 or RB8 external relay junction box to the PWC OUTPUT connector. When the displayed
weight is equal to or greater than the preset weight (see KEYPAD FUNCTIONS: PRESET key), the
PWC output changes from 5 volts dc to 0 volts dc or from 0 volts dc to 5 volts dc (see PRESET
WEIGHT COMPARATORS, Undr1= in the CALIBRATION section) and will drive solid state relay
resistive loads of 200 ohms or greater.
PIN NUMBER FUNCTION
10 ............ PWC #1 OUT
2 ............. PWC #2 OUT
1 ............. PWC #3 OUT
9 ............. PWC #4 OUT
11 ............ PWC #5 OUT
13 ............ PWC #6 OUT
5 ............. PWC #7 OUT
4 ............. PWC #8 OUT
12 ............ COMMON
PIN NUMBER... FUNCTION
7 ............. GROUND
19 ............ GROUND
2 ............. Tx D
3 ............. Rx D
11 ............ Tx D RETURN
13 ............ Rx D RETURN
10 ............ Tx D SRC
12 ............ Rx D SRC
23 ............ Tx D ACTIVE
25 ............ Rx D ACTIVE
24 ............ GROUND
9 ............. +5 VDC
6 ............. +5 VDC
PIN 8
PIN 1
PIN 9
PIN 15
PWC Output
figure no. 5 - preset weight comparator output
BI-DIRECTIONAL SERIAL INTERFACE (Serial I/O)
An RS23220mA compatible bi-directional serial interface
connector is located on the back of the instrument and may
be used for various functions. It will accept serial commands*
allowing the 748 to be controlled remotely. Figure no. 6
illustrates the pin layout for this connector.
* See SERIAL INPUT COMMANDS section for details.
figure no. 6 - bi-directional interface
Serial I/O
INTERCONNECT CABLE - Example A
CONNECTION DIAGRAM
for 20 mA
CURRENT LOOP OPERATION
Peripheral Device has
PASSIVE END
of Current Loop
(standard enclosure only).
+Y
TX SOURCE 10 RX RETURN
TWISTED PAIR
TX RETURN 11 RX ACTIVE
TX ACTIVE 23
- - - - - - - - - 24
RX SOURCE 12 TX RETURN
TWISTED PAIR
RX RETURN 13 TX ACTIVE
RX ACTIVE 25
- - - - - - - - - 24 CHASSIS GND
INTERNAL
CIRCUITRY
PERIPHERAL
DEVICE;
PASSIVE END
SERIAL
CONNECTOR;
ACTIVE END
Refer to
applicable
information for
required
connections.
RX RETURN 13 TX SOURCE
TWISTED PAIR
RX ACTIVE 25 TX RETURN
TX RETURN 11 RX SOURCE
TWISTED PAIR
TX ACTIVE 23 RX RETURN
CHASSIS GND
INTERNAL
CIRCUITRY
PERIPHERAL
DEVICE;
ACTIVE END
SERIAL
CONNECTOR;
PASSIVE END
Refer to
applicable
information for
required
connections.
INTERCONNECT CABLE - Example B
CONNECTION DIAGRAM
for 20 mA
CURRENT LOOP OPERATION
Peripheral Device has
ACTIVE END
of Current Loop
(standard enclosure only).