Watlow Controller Series D8, Руководство пользователя

Страница: 78 / 179

D8 Series User’s Guide
Chapter 4: Operation and Setup
78
D8
Furnace
Power
Controller
To Data
Logger
Loop 1 PID Output
Loop 2 PID Output
Heater
Loop 1
Input
Process
Variable
Serial
DAC
Figure 4.8 – Application Using Process Variable Retransmit
Table 4.8 shows the parameter setup for this example.
Table 4.8 – Parameters Settings for Process Variable Retransmit Example
MENU PARAMETER VALUE COMMENT
PV retrans Ht output retrans PV 1
Choose to retransmit the loop 1 process
variable.
PV retrans Ht retrans LowPV 0°F
This is the input value represented by a 0
percent output signal. The recorder input
is a linear 4 to 20mA signal representing a
range of 0°F to 1000°F, so we will use a 0
percent output signal to represent 0°F.
PV retrans Ht retrans HighPV 1000° F
This is the input value represented by a 100
percent output signal. The recorder input
is a linear 4 to 20mA signal representing a
range of 0°F to 1000°F, so we will use a 100
percent output signal to represent 1000°F.
PV retrans C1 output retrans none
Not using the cool output of loop 2 to
retransmit a process variable.
To complete this configuration, the output for loop 2 must be configured to provide the 4 to 20mA
analog signal (via the Serial DAC) that is required by the data logger.
When setup is completed, the controller will produce an output on loop 2 which is linear and
proportional to the loop 1 process variable.