Samson 5179 System-widefunctions, Example to determine the limit value, 30 kW, = 30 pulse / h

System-wide functions

A heat meter with pulse output connected at input Vmax (terminal 30) can be used either to limit the system flow rate (parameter code: U) or the system capacity (parameter code: P). The pulse weighting of the heat meter (WMZ) and the type of limitation selected must be entered. The dis- played value corresponds to the unit l/pulse or kWh/pulse.

When the pulse rate reaches the current maximum limit, the flow set point of the control circuit RK1 is reduced. How strongly the controller responds is determined by the Proportional-action coefficient for limitation.

Example to determine the limit value:

If a capacity of 30 kW is to be limited, the following limit value must be set for a heat meter with an output of one pulse per kilowatt-hour:

P =	30 kW		= 30 pulse / h
	1 KWh / pulse
Settings for capacity limitation
Functions		WE		Configuration
Limitation of heat meter (WMZ)		OFF		Co5 -> Fb08 = OFF
Pulse input for flow rate or capacity limitation		OFF		Co5 -> Fb09 = ON, select: P
				CONST:	Limitation constant
				4-Pt:	Limitation acc. to
		10			4-point characteristic
				Pulse weighting / 0.1 to 10
Parameters		WE		Parameter level / Range of values
Maximum capacity of the entire system		50 kW		PA5 / 0.1 to 5999 kW
Maximum capacity of the DHW heating		50 kW		PA5 / 0.1 to 5999 kW
Proportional-action coefficient for the limitation		1.0		PA5 / 0.1 to 10
Select CONST additionally for:
Maximum capacity of the heating		50 kW		PA5 / 0.1 to 5999 kW
Select 4-Ptadditionally for:
Outdoor temperature Point 1		–15 °C		PA5 /–30 to 90 °C
Point 2		– 5 °C
Point 3			5 °C
Point 4		15 °C
Maximum capacity limitation, points 1 to 4		50 kW		PA5 / 0.1 to 5999 kW

EB 5179 EN 65