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Building Technologies   Basic documentation LMV37.4...  CC1P7546en 
  7 Basic unit LMV37.4  17.12.2018 
7.5.3.3.  Safety phase (phase 01)  
 
The safety phase is an intermediate phase which is completed prior to triggering 
lockout. The relays of the fuel valves and the safety relay (fan) are deenergized, but 
lockout does not yet take place. The alarm relay is not yet activated. If possible or 
permitted, safety checks or repetition counter checks are made whose results decide on 
the transition to Lockout phase or Standby. The duration of the safety phase is dynamic 
(depending on the extent of testing), the maximum time being 30 seconds. 
This process is aimed primarily at avoiding unwanted lockouts, e.g. resulting from EMC 
problems.