Installation manual

Control Parameters
900M050U00  Athena Controls, Inc. 8-3
8.2 Configuring Control Parameters for On/Off Control
8.2.1 Introduction
On/off control has two states, fully off and fully on. To prevent rapid cycling, the
controllers allow you to configure a deadband and a hysteresis value as described in
1.5.3.
8.2.2 Specifying the Deadband for On/Off Control
Parameter Name
: Deadband for Output 1 (20) and Deadband for Output 2 (37)
Name as Displayed
:
db.1db.1 and db.2db.2
Used By:
all controllers
When Displayed:
if output type is on/off
Range:
RTD and thermocouple input types: negative sensor span to
positive sensor span
linear input types: limited by the scaling defined for the input
using the input menu (See Note 1 below.)
Default:
1
Description:
If a deadband value is applied to an output, it has the effect of
shifting the setpoint and the hysteresis for that output. That is,
the deadband for each output moves the “off” transition away
from the setpoint, and pushes the “on” transition away by an
equal amount. For a heating (reverse-acting) output, a positive
deadband value moves the setpoint used by the controller below
the displayed setpoint. For a cooling (direct-acting) output, a
positive deadband value moves the setpoint used by the
controller above the setpoint displayed. (A negative deadband
value has the opposite effect.)
Note 1: The range is reduced when a linear input is used and the value of the dSPLdSPL
(display) menu dEC.PdEC.P (decimal position) parameter is not 0 (zero). See 4.3.2 for more
information about the effect of a linear input on numerical ranges.