Watlow EZ-ZONE RM Limit Module Rev C - Manual (Page 119)

Watlow EZ-ZONE ® RML Module • 116 • Appendix
Indication Description Possible Cause(s) Corrective Action
No Serial Communi-
cation
Cannot establish serial com-
munications with the con-
troller
• Address parameter incorrect
• Incorrect protocol selected
• Baud rate incorrect
• Parity incorrect
• Wiring error
• EIA-485 converter issue
• Incorrect computer or PLC communi-
cations port
• Incorrect software setup
• Wires routed with power cables
• Termination resistor may be required
• Set unique addresses on network
• Match protocol between devices
• Match baud rate between devices
• Match parity between devices
• Correct wiring issue
• Check settings or replace converter
• Set correct communication port
• Correct software setup to match con-
troller
• Route communications wires away
from power wires
• Place 120 Ω resistor across EIA-485
on last controller
Device Error
[`100]
[rEtn]
Controller displays internal
malfunction message at
power up.
• Controller defective
• Sensor input over driven
• Replace or repair controller
• Check sensors for ground loops, re-
verse wiring or out of range values.
Remote User Inter-
face (RUI) menus
inaccessible
Unable to access [`SEt],
[OPEr] , [FCty] or [ProF]
menus or particular prompts
in Home Page
• Security set to incorrect level • Check [`loC] settings in Factory Page
• Enter appropriate password in [UloC]
setting in Factory Page
• Digital input set to lockout keypad • Change state of digital input
• Custom parameters incorrect • Change custom parameters in Factory
Page
RUI value to low
[ual;l] Value to low to be displayed
in 4 digit LED display
<-1999
• Incorrect setup • Check scaling of source data
Detection of and Rules Around Abnormal Sensor Conditions
Inputs Detection of Abnormal Conditions
Thermocouple
Shorted No direct detection, Open loop firmware detection.
Open Yes, Parasitic pull-up
Reversed Yes, firmware detection
Current Source
Shorted Range limiting only
Open Range limiting only
Reversed Range limiting only
Voltage Source
Open Range limiting only
Shorted Range limiting only
Reversed Range limiting only
RTD
S1 open Yes, pulled up.
S2 open Not implemented.
S3 open Yes, pulled up.
S1 short to S2 Yes, pulled up
S1 short to S3 Yes, pulled down to under range.
S2 shorted to S3 Not implemented, Possible, monitor S2 voltage.
S1 and S2 open Yes, pulled down to under range.
S1 and S3 open Yes, S1 pulled up.
S2 and S3 open Yes pulled up.
Thermistor
S1 open Yes, pulled up to sensor over range.
S3 open Yes, pulled up to sensor over range.
S1 short to S3 Yes, pulled down to sensor under range.
S1 and S3 open Yes, S1 pulled up to sensor over range.