Bryant 548J Heat Pump User Manual


 
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Table 18 Manufacture Date
When troubleshooting, you may need to know a control module’s manufacture date.
Obtain the manufacture date from
a...
Notes
Module status report (modstat) To obtain a modstat with BACview
6
:
1. Press Function (FN) key and hold.
2. Then press period (.)
3. Release both buttons.
ThereportshowsthedateunderMain board hardware.
Sticker on the back of the main control
module board
“Serial No: RMPYMxxxxN”
(Bar Coded & Typed Number)
The serial numbers are unique and contain embedded information:
“RMP” --- These first th ree digits are uni que to RTU---MP a nd are us ed as an identifier.
“YM” --- These two digits identify the last digit of the year and mont h (in hex, A=10/Oct)
of manuf acture. “74” would represent a date of manufacture of “April 2007”.
xxxx” --- These four digits represent the sequential number of units produced for a given
product for the mentione d manufacturing time period.
“N” --- This final digit represents the decade and toggles between “N” and “M” every
ten years.
Table 19 Basic Protocol Troubleshooting
Problem Possible cause Corrective action
No communication wi th 3rd
party vendor
Incorrect settings on SW1, SW2 and SW3 Verify and correct switch settings. Cycle
powertoRTU---MPafterchangingswitch
settings.
RS485 Port has no v ol tage output
(check with RTU---MP disconnected from RS485
communication bus):
• Bacnet @ 9600/19.2K --- .01 to .045vdc
• Bacnet @ 38.4K --- .06 to .09vdc
• Bacnet @ 76.8K --- .1vdc
• Modbus @ 9600 --- 76.8K --- .124vdc
• N2 @ 9600 --- .124vdc
• LON @ 9600 --- .124vdc
Verify RTU---MP has correct power supply.
Possible bad driver on board.
Check RS485 bus for external voltage,
shorts or grounding before r econnecting
to th e bus .
Verify devices are daisy chained and repeaters and bias
terminators are correctly installed.
Check 3rd party vendor RS485
communication wiring guidelines and
troubleshooting procedures.
Table 20 Modbus Excep tion Codes that May be
Returned From This Controller
CODE NAME MEANING
01 Illegal Functi on
The Modbus function code used
in the query is not supported by
the controller.
02 Illegal Data Address
The register address used in the
query is not supported by the
controller.
04 SlaveDeviceFailure
The Modbus Master has
attempte d to write to a
non---existent register or a
read---only register in the
controller.
Modbus
1. Verify that the BAS and controller are both set to
speak the Modbus RTU protocol. The protocol of the
controller is set via SW3 (switches 3, 4, 5, and 6).
The protocol can also be verified by getting a Modstat
of the controller through the BACview. Hit the “FN”
key and the “.” key at the same time to pull up a
Modstat. Scroll to the bottom of the page and there is
a section entitled “Network Communications.” The
active protocol and baud ra te will be shown in this
section.
2. Verify that the BAS and controller are set for the
same baud rate. The ba ud rate of the controller is set
via SW3 (switches 1 and 2). The baud rate can also
be verified via the BACview by obtaining a Modstat
(see above).
3. Verify that the BAS is configured to speak 2 -- wire
EIA--485 to the controller. The BAS may have to
configure jumper or DIP switches on t heir end.
4. Verify that the BAS and the controller have the same
communication settings (8 data bits, No Parity, and 1
stop bit).
5. Verify that the controller has a unique Modbus slave
address. The controller’s Modbus slave address is set
by its rotary address switches.
6. Verify that the BAS is using the proper Modbus
function codes to access data from our controller.
Supported function codes are shown above.
7. Verify proper wiring between the BAS and the
controller.
8. Verify that the BAS is reading or writing to the proper
Modbus register numbers on the controll er. Download
the latest points list for the controller to verify.
9. Verify that the BAS is sending his requests to the
proper slave address of our controller.
NOTE: See RTU-- MP 3rd Party Integration Guide (or
alternatively Form 48--50H--T--1T, Appendix) for Modbus
Protocol Conform ance Sta tement.
548J