User`s manual
Western Reserve Controls, Inc. 1782-JDC User’s Manual
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is not supported in the 1782-JDCx) requires two additional signal lines on the serial side and
it controls the data before it is received.
16. When should I turn Pad Mode ON? Or what configuration parameter should I check
when the scanner cannot stay connected to the 1782-JDCx due to an IO size error?
If the DeviceNet scanner or the master device needs to be pre-configured with an input
(produce) size before making a connection, or if the serial device will be sending variable
data size strings, you will need to turn the PAD Mode ON. This parameter should be
checked if the 1782-JDCx will not stay connected due to an IO size error.
17. What should my master device logic be doing to see if new data is present in a poll
message?
The Master program logic should be looking at the Receive Record Number and comparing
it with the last stored record number to monitor new data arrival in Immediate (Non-
Handshake) Mode. In the Master Handshake mode, the program should be looking at the
New Data bit in status and if detected, should supply the new record number and wait for
the 1782-JDCx to produce data along with that record number.
18. What does the 1782-JDCx require for power?
The 1782-JDCx receives all necessary power from the DeviceNet network cable. This
should be between 11 and 25 Vdc. It consumes about 2 watts of power maximum.
19. Where should I use a 1782-JDCx gateway vs. a 1799wr-DASCII gateway?
The 1782-JDCx has a form factor designed for DIN rail mounting and the 1799wr-DASCII is
designed for panel mounting. The 1782-JDCx models are functionally very similar to the
1799wr-DASCII. The additional parameters of the 1782-JDCE-1 are most similar to the
1799wr-DASCII and offer some additional flexibility. Also the 1799wr-DASCII is designed
for RS232/422/485 serial communication, whereas the 1782-JDCx models are designed for
a specific serial communication type.
20. How do I access the serial ASCII data from a 1782-JDCx gateway?
When configuring your PLC, you have the option to memory map the ASCII data from the
1782-JDCx to a location on your PC. The ASCII data can be found at this location.
21. When do I need to use an EDS (electronic data sheet) file for a 1782-JDCx gateway?
An EDS file is not necessary, but it makes configuring the 1782-JDCx (changing baud rate,
framing, etc.) far easier than if you were to try to change the device parameters by editing
the attributes of certain class objects and instances without the aid of a configuration tool.
There are many software configuration tools available with EDS readers that can be used to
set up the device.
22. What is the proper cable to use for a 1782-JDCx gateway serial connection?
The proper cable selection depends upon which gateway model is used, the serial
communication baud rate desired and the total cable length. Cable selection guidelines:
1782-JDC-1: RS232 – 3 wire shielded
1782-JDC-2: RS485 – 3 wire shielded
1782-JDC-4: RS485/RS422 – 3 wire (RS485) shielded or 5 wire (RS422) shielded
1782-JDCE-1: RS232 - 3 wire shielded
23. Where can I purchase the proper cable for a 1782-JDCx gateway serial connection?
You can purchase the proper cable from many suppliers and fitted with the connectors
required for the gateway model and serial device being used.