Vaisala Indigo200, Руководство пользователя

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6.3 Setting relay activation limit using hysteresis
If the measurement you are using to control the relay is likely to move back and forth close to
the activation setpoint, you can set a hysteresis that prevents the relay switching on and off
too frequently.
When hysteresis is used, the relay activates at the defined limit, but does not switch off
immediately when the measurement moves back to the other side of the activation limit.
Instead, with hysteresis, the relay remains active until the measurement reaches the defined
tolerated variation limit.
Figure 22 Relay settings example: one setpoint with hysteresis
To define a single setpoint for relay activation when the measurement falls below the defined
activation limit ( Activate below ) using hysteresis:
1. Select to access Insight main menu.
2. In the Configure Device menu, select either relay A or relay B.
3. Enable the relay output by setting Relay output on/off to ON.
4. Select the measurement parameter that is used to control the relay with the Output
parameter dropdown.
The parameter options depend on the connected probe. Note that the parameter units are
defined in the Settings menu: see Unit settings (page 26) .
5. Enter the activation limit value in the Activate below field.
6. Leave the Activate above field empty.
7. Enter the hysteresis value in the Hysteresis field.
8. Select the Error output state for the relay.
Indigo201 User Guide M212842EN-B
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