SMAY iSWAY-FC, Руководство по эксплуатации и обслуживанию

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Operation and Maintenance Manual (DTR) iSWAY
®
Set of products
Version 1.8 of 2.2021 55
Fig. 11.24. Static pressure measurement point (wall mounted version).
The measurement of pressure in the protected space and reference pressure is carried out at a
properly located and prepared measuring point (Fig. 11.23) and (Fig. 11.24). The impulse tube
inside the measuring point should be terminated with a T-piece manifold. The wall version
requires 2 holes on the sides of the box, when installed outside the building, also 2 holes at the
bottom of the box should be made for dehydration.
12. FireBUS ® bus loop
FireBUS
®
is a bidirectional annular data bus with a fixed transmission direction at system
startup. The transmission of information between devices takes place via a differential voltage
signal according to RS485 standard at 115200 [bps]. Physical connections between devices are
shielded, insulated, protected against surges and current. The possibility of hardware short-
circuiting of receiving lines with transmitting lines for individual bus nodes allows for very fast
information transfer. Hardware short-circuiting of receiving and transmitting lines is carried out
automatically via software.
The bus allows for multi-level communication between the regulators, pressure and temperature
sensors that are part of the differential pressure system on a given object. The FireBUS
®
bus
enables all the devices on a given site to be connected to one network with one decentralized
monitoring and fault detection system. Devices that are part of the FireBUS
®
bus include two bus
types: FireBUS
®
global and FireBUS
®
local.
Each of the devices on the bus can act as a master, but there can be one master on the bus at any
one time. The devices transfer the master function to each other during system operation.
Initialization of a given bus and the process of passing the access is initiated by one of the
regulators in the network, which acts as an active monitor additionally monitoring the status of
devices included in the given FireBUS
®
bus and monitoring the correctness of information
transmitted on the given bus.
The FireBUS
®
bus is equipped with a number of mechanisms protecting against line interruption
or damage to one of the devices in the network.
If a failure is detected on a line or one of the devices, all devices on the bus shall be switched to
emergency communication mode which continues to provide effective fire protection in aerated
rooms.
Bus interruption and short circuit resistance:
- One interruption/shortening, anywhere on the loop (wires D+ or D-), does not change the