Description

This function block set is used to control the start and stop of an on-off humidifier. If the current humidity is below the subtraction of start/stop differential from the setpoint, the humidifier turns on; if it is above the sum of the start/stop differential and the setpoint, the humidifier turns off.

The humidifier is required to be switched off immediately in the event of a fault alarm.

Function

When "Fan Command" is "1" (0-OFF/1-ON) and "Humidity Input" is lower than the subtraction of start/stop differential from the setpoint, "Humidifier Command" is "1".

When "Fan Command" is "1" (0-OFF/1-ON) and "Humidity Input" is greater than the sum of the start/stop differential and the setpoint, "Humidifier Command" is "0".

When "Fan Command" is "0" (0-OFF/1-ON) or "Sensor Fault Alarm" is "1" (0-OK/1-FLT), "Humidifier Command" is "0".

Internal logic

Input

PIN

Data type

Unit

Default value

Value/range

FAN_CMD

BOOL

-

0

0-OFF / 1-ON

FAULT

BOOL

-

0

0-OK / 1-FLT

HUM_PV

FLOAT

%

0

0...100 %

HUM_SP

FLOAT

%

50

0...100 %

HYS

FLOAT

%

6

0...100 %

Output

PIN

Data type

Unit

Default value

Value/range

HUM_CMD

BOOL

-

-

0-OFF / 1-ON

Example