1 loss of signal display, 4 serial data output, Loss of signal display – Rice Lake EL232 XPCD Explosion Proof Remote Serial Display User Manual
Page 22: Cl(+) out, Cl(-) out
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EL232 XCPD Installation Manual
3.3.1
Loss of Signal Display
Press the Reset switch to enter new values into the
E L 2 3 2 X P C D , o r t u r n o ff t h e p ow e r, o r wa i t
approximately 30 seconds and the EL232 XPCD will
reset itself.
The following tables illustrate switch settings for the
loss of signal display.
3.4
Serial Data Output
The EL232 XPCD comes standard with an active 20
mA current loop transmitter which echoes the serial
data received by the EL232 XPCD. This data is
echoed as a 20 mA loop regardless of whether the
input source was RS232 or current loop.
The output is active and supplies current from a
voltage source of approximately 8 VDC. The current
transmitter is an HP-4100 and can transmit data
cleanly at 9600 baud. The HP-4100 supplies mark
currents of >12 mA and space currents of <2 mA.
Certain scale industry remote displays and printers use
darlington type optocouplers as input devices.
Unbiased 4N33 type opto isolators can be turned on
by 2 mA. These are not true current loop receivers. If
a device which the EL232 XPCD is transmitting to
cannot properly receive the data, change the 4N33 to a
4N25 opto isolators and the problem will normally
disappear.
Figure 3-10 illustrates how to connect the current loop
output of the EL232 XPCD.
Figure 3-10. 20 mA Active Current Loop Output
You can check the current loop output with a simple
jumper connected between pin J2-3and J2-4. The
LED on the CPU should flash on and off when data is
transmitted.
Note:
When using a passive current loop input, the serial
output is not available. Consult the factory for additional
information.
Indicator
Indicator Type
SW1-3
SW1-4
SW1-5
SW1-6
Condec
On
On
On
On
General Freedom
Off
On
On
On
Electro 560
On
Off
On
On
A n D
Off
Off
On
On
WI-110, WI-120
On
On
Off
On
Toledo
Off
On
Off
On
Flexweigh
On
Off
Off
On
Analogic
Off
Off
Off
On
Masstron
On
On
On
Off
Fairbanks
Off
On
On
Off
Streeter Richardson
On
Off
On
Off
Cardinal 738
Off
Off
On
Off
Generic
Off
Off
Off
Off
Table 3-3. Indicator Switch Settings
Loss of Signal Display
Display
SW1-7
Last data
Off
- - - - - -
On
Table 3-4. Loss of Signal Display
Input Signal Type
Interface
SW1-8
RS232
On
20 mA
Off
Table 3-5. Input Signal Type
GND
K4
K3
K2
K1
+5V
CL4 IN-
CL4 IN+
CL3 IN-
CL3 IN+
CL2 IN-
CL2 IN+
CL1 IN (-)
CL(+) OUT
J2
CL(-) OUT
CL1 IN (+)
RS-232 (+)
RS-232 (-)