Control mechanism "without separation of functions", used in fire ventilation cut-off dampers – current control

Control mechanism "without separation of functions", used in fire ventilation cut-off dampers – current control.

In this case, the combined electromechanical rotary actuator is responsible for moving the damper to the safety position and its return to the waiting position. In the event of a fire detected by SAP, the current signal is transmitted from the CSP to the control mechanism of the cut-off fire ventilation damper in the hazardous area. This causes the opening of the fire ventilation shut-off dampers in this zone as a result of the operation of the electric motor being the basic element of the combined electromechanical rotary actuator.. In the remaining zones, the dampers remain unchanged and their mechanisms remain deenergized. The damper is restored to the waiting position as a result of the operation of the electric motor of the compound actuator after re-energizing the power supply via an interface that allows separation of the safety functions from the comfort of restoring the waiting position, which should be installed on the damper or in its immediate vicinity. This action should follow the activation of the remote-restoration switch from the zone to standby, in which the intervention was performed or by manually arming the flaps, which are not equipped with the remote recovery standby function. In this way, the obligation to verify by the facility security services each fire hazard signal in place is enforced, from which this signal comes, before the normal functioning of the CSP is restored. Mechanisms of this type, in addition to the control energy to change the position state from the waiting position to the safety position, require energy to be supplied, which enables the operation of the electric motor of the rotary actuator. In most cases, limit switches are also built inside the actuator, which signal the beginning and end of each change of the damper partition position. This type of actuators also have the option of manually changing the position of the damper in order to check its correct operation after installation or during a service inspection.. However, the function test is time-consuming, because it is implemented with a crank, which allows you to manually change the position of the flap. pay attention, that in the case of using "non-functional separation" current controlled control mechanisms, the time needed to move to the safety position of the flap or return to the waiting position is approx 60 s, which is related to the operation of the electric motor of the actuator. Due to the need for electricity supply, in order to allow the damper to move to the safety position, it is essential that:
– the power supply was realized via a power supply cooperating with a battery of batteries,
– in the case when the cable connecting the controller with the interface and the combined damper actuator is longer than 2 the connection was monitored.

Pay attention once again, that as per your requirement, fire ventilation cut-off dampers designed to work in installations, in which one-station implementation of procedures for controlling devices constituting fire protection was adopted, must open on command 2 min after the start of the test, and the opening time cannot be longer than 2 min. Means, that the temperature in the test furnace is then around 100 ° C. Composite cylinders, on the other hand, in most cases have a specific nominal operating temperature of 50 ° C, which may mean, that the opening of the damper under the conditions specified in the above-mentioned requirements. draft standard (a corresponding to the initial stage of fire development) current-controlled actuator without function separation, will not be possible without the actuator being protected by a fireproof housing. The fact is also important information, that on the day of submitting the Guide for printing, there were no fire ventilation dampers on the Polish market, which have been tested in accordance with the above-mentioned. requirements to be confirmed, is it possible to use current-controlled composite cylinders without "separation of functions" without a fireproof housing.

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