User Instructions
www.pulsar.pl   EN54M   RED POWER plus 
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5.6.2 Cooperation with electric actuators - EN54C-LS4 and EN54C-LS8 sequential modules. 
The sequential modules are designed for use with electric actuators without return spring (EN54C-LS4) 
and  with  electric  actuators  with  return  spring  (EN54C-LS8)  used  for  fire  dampers  and  smoke  vents.  These 
devices are used in fire alarm systems and smoke and heat control systems.  
When switching on the electric actuator, a short-term current surge, exceeding its rated current, may 
occur. If multiple electric actuators are connected, the above-mentioned surge current poses a risk of incorrect 
operation of the power supply (e.g. triggering the protection of output circuit), despite not exceeding the current 
capacity of the power supply.  
The  sequential  switching  module  causes  the  receivers  connected  to  its  outputs  to  be  sequentially 
switched, with a delay of 100 ms. Thanks to this solution, the surge current is reduced to the value ensuring 
correct operation of the power supply. Thus, it enables safe connection of additional actuators. All outputs are 
independently protected by PTC polymer fuses and have LED diodes signaling the activation of each output. 
The module is controlled by a control device (e.g. a CSP control panel) configuring the resistance at the 
INPUT connector. The technical output of failure signals failures at the parametric INPUT input. 
Fig. 11. Example of connection of the EN54C-LS8 sequential module with actuators with return spring. 










