Operating hours counter
- Block name
- ST call
- Library
- Version
- Description
- Inputs
- Outputs
- Function
- Application example

Operating hours counter

Block name

T32_OPERATING_HOURS

ST call

PROGRAM TEST_T32
   VAR 
        BOOL1,BOOL2,BOOL3: BOOL;
        TIME1,TIME2:TIME;
       DT1: DT;
        FB: LIB.HVAC.V1_0.T32_OPERATING_HOURS;
  END_VAR
 FB(BSET:= BOOL1, ENABLED:= BOOL2, IN:= BOOL3,TINIT:= TIME1, OUT=> TIME2, TSET=>DT1);  
END_PROGRAM

Library

LIB\HVAC

Version

V1.0

Description

The block measures total activity time of a binary input, or cumulated operating time of the connected aggregate (pump, fan, boiler).

Inputs

Input	Type	Description	Default value
BSET	BOOL	Rising edge sets the counter to TINIT	False
ENABLE	BOOL	This input must be TRUE for the block to operate	False
IN	BOOL	Activity input	False
TINIT	TIME	“Starting” value after reset, usually 0	0

Outputs

Output	Typ	Description
OUT	TIME	Total time the IN input was in TRUE
TSET	DT	Date and time of last reset (rising edge on BSET) as UTC

Function

The block acts as a stopwatch. Time measuring start is activated by bringing the IN input to True, and stopped by bringing IN to False. The default state is set by a rising edge at bset, while the block writes the TINIT value to the OUT output rather than the cumulated time. This becomes the starting value for further cumulation. TSET records the rising edge time.

Application example

The variable PUMP1FB gives the pump operation signal. The cumulated time is recorded in T32 and of the total operation time exceeds PUMP_SERVICE_TIME, an alarm to call for service inspection is generated.

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