Input H1 / H2
Minimum flow temperature
setpoint H1 / H2
Siemens Schweiz AG
Input H1 generates a controller-internal error message.
If the "Alarm output" (relay outputs QX2-4, operating lines 5891 – 5894) is appropriately
configured, the error message will be forwarded or displayed by an additional contact
(e.g. external lamp or horn).
Minimum flow temperature setpoint TVHw
The adjusted minimum flow temperature setpoint will be activated via terminals H1/2
(e.g. an air heater function for a warm air curtain) closes its contact.
Excess heat discharge
Active dissipation of excessive heat enables an external heat source to force
consumers (heating circuit, DHW storage tank, Hx pump) to draw excessive heat by
delivering a forced signal.
Using parameter "Excessive heat draw", it is possible to select for every consumer
whether or not the forced signal shall be considered, thus deciding whether or not the
consumer shall contribute to the dissipation of heat.
• Local effect
When using LPB device address 0 or >1, excessive heat dissipation only acts on the
local consumers connected to the controller.
• Central effect (LPB)
When using LPB device address = 1, excessive heat dissipation also acts on the
consumers connected to the other controllers in the same segment.
The distribution of excessive heat from segment 0 across other segments of the system
is not possible.
Normally closed contact (NC)
The contact is normally closed and must be opened to activate the selected function.
The contact is normally open and must be closed to activate the selected function.
Function "Min flow temp setpoint" on operating line 5950 is activated via contact H1.
The boiler maintains the temperature level set here until contact H1 opens again or until
a higher heat request is delivered.
If several heat requests are received at the same time (LPB, contact H1, DHW, or from
the controller itself), the highest of them will automatically be selected.
minimum flow temperature setpoint
Flow temperature setpoint
The settings in detail
22. November 2006