Vaisala Indigo 202 - Setting Relay Activation Limit Without Hysteresis

Relay State Information
W
hen one or both relays are enabled, the relay state (active/not active) is shown on the
optional display. You can also check the status of the relays in the Status view of the wireless
configuration
interface.
Figure 20 Relay Icons on the Optional Display (Relay A Active, Relay B Not Active)
Relay Activation Setpoint and Hysteresis
You can
define whether the relay is activated when the measurement falls below a set limit
(Active below trigger level), or when the measurement exceeds a set limit (Active above
trigger level). To prevent the relay switching back and forth when the measured value is
near to the setpoint value, you can set a hysteresis with the Low Trigger Level and High
Trigger Level settings.
For example, if you want the relay to activate when the measurement exceeds (Active
above trigger level) 2000 units, but do not want the relay to switch o if the measurement
momen
tarily falls between 2000 and 1980 units, set the High Trigger Level to 2000 and
Low Trigger Level to 1980. With this configuration, the relay activates when the
measur
ement exceeds 2000, but does not switch o until the measurement falls below
1980.
6.2 Setting Relay Activation Limit
W
ithout Hysteresis
You can set the relay to activate when the probe measurement exceeds or falls below a set
limit. W
hen you configure a single setpoint for relay activation without hysteresis, the relay
switches on or o immediately when the measurement moves over or below the setpoint
(
depending on the low/high activation mode selection).
When you enter a value into a field, the value is saved automatically when you exit the
input field (for example, tap on an area outside of the field).
Indigo 202 User Guide M211966EN-A
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