Raypak 5000.72A, Installation & Operating Instructions Manual

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Modbus Operating Mode Selection
(MODBUS)
This allows the system integrator to select the Modbus
operating mode. The choices are “OFF”, monitor
(MNTR), temperature control (TEMP) and rate control
(RATE). The default setting is “OFF”.
Modbus Component Address
(ADDRESS)
This assigns a slave address to components on the
Modbus communication network. The range of adjust-
ments is 1 to 247. The default value is 1.
Modbus Data Type (DATA TYPE)
This assigns the Modbus data type. The options
include “RTU” and “ASCI”. The default is “RTU”.
Modbus Communication Baud Rate
(BAUD RATE)
This assigns the communication speed for the Modbus
communication network. The choices include: 2400,
9600, 19K2, 57K6 and 115K. The default value is
19K2.
Modbus Parity (PARITY)
The choices are “NONE”, “EVEN” and “ODD”. The
default is “EVEN”. 1 stop bit is used for “EVEN” or
“ODD”. 2 stop bits are used for “NONE”
Heater Mass (BOIL MASS)
The heater mass setting (1 or 2) allows the installer to
adjust the VERSA IC
®
Control to the thermal mass of
the system. The heater mass setting automatically
determines the preliminary PID modulation parame-
ters.
Boiler Pump Purge (BOIL PURGE)
The VERSA IC
®
Control continues to operate the boil-
er pump after the burner shuts down for the time
selected. When BOIL PURGE is set to OFF, there is
no boiler pump post purge. The default timing is 3:00
min, but can be adjusted from 20 sec to 10 minutes.
NOTE: Always start with a heater mass setting of 2
(Default).
CAUTION: Continuous pumping through the unit is
not supported and may cause a non-warranty failure.
Heater Mass Definitions
Mass = 1 Fast response,
Mass = 2 Standard response
Table K: Mass parameters