User guide

I-E67-84-1B February,2002 8-27
Setpoint Relay Output (Basic/Advanced)
A Setpoint Relay Output can be configured to
energize when the Process Variable or
Temperature exceeds (i.e., a High Setpoint) or
falls below (i.e., a Low Setpoint) a defined
level. Valid Setpoint values are limited to
the Process Variable and/or Temperature range
of the TB84PH Advantage Series analyzer. See
Table 1-3, Specifications, for analyzer range
values.
To prevent relay chatter, a Setpoint Relay
Output has an configurable Deadband. The
Deadband control keeps the relay energized
until the Process Variable or Temperature has
decreased below a High Setpoint value or above
a Low Setpoint value by the Deadband value.
Valid Deadband values are 0.00 to 10.00 pH for
pH, 0 to 200 mV for ORP and pION, 0 to 10% of
the END.MAG (i.e., End Magnitude) for Ion
Concentration Process Variable sources and 0
to 10 C (18 F) for Temperature sources.
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A Time Delay control also refines the function
of a Setpoint Relay. Entering a Time Delay
value greater than 0.0 minutes enables a
waiting period before energizing the relay
once the setpoint condition has been met.
Valid Time Delay values are 0.0 to 99.9
minutes.
Set the Setpoint parameters of a Relay Output
using Figure 8-11 as reference and the
following procedure:
1) Set the Setpoint (i.e., LO SPT or HI SPT)
using the Key to increment the
blinking digit and the Key to move to
the next digit, and press the ENTER Key
to enter the new value.
2) Set the Deadband (i.e., DBAND) using the
Key to increment the blinking digit and
the Key to move to the next digit and,
press the ENTER Key to enter the new
value.