Cable tray fittings : Names and functions

 

  Methods of programming Addressable fire alarm detectors

The fire alarm detectors in addressable systems are programmed in several ways depending on the detector's manufacturer these methods are : 

1) Using " address card "

2) Using " electronic programming device "

3) Using " DIP switches "

4) Using " decimal address switches "

5) Automatic addressing 

1) Using "address card"

A card contains several buttons is used and each button has a number beside it as follows : 1 , 2 , 4 , 8 , 16 , 32 , 64 and this card is fitted in the detector base .

To obtain a specific address with a specific number, one or many buttons (each button has a number written beside it) are removed so that the sum of the numbers beside removed buttons gives the required address as shown in the next figure :

Suppose we need to get an address (10) so the two buttons that have the numbers 2 and 8 should be removed as their sum (2+8) equals 10 .

2) Using Electronic programming device 

In this method , the detector is connected to a special electronic programming device which has a small screen and keyboard and the programmer can write the address using the keyboard and read the address through the small screen .

detector programming device

3) Using DIP switches

DIP stands for Dual In-line Package
In this method DIP switches are fitted in the detector base as in the following fig :

Each switch has two positions (on , off) and there are 8 switches (1 through 8) all of them work in binary
As we said before the switch has two positions (on,off) , the position off means zero but the position on of the switch gives the values stated in the following table :

Example : if we want to give an addressable detector an address of (99) we will take the following steps:

• The switch "1" is turned on and get 1
• The switch "2" is turned on and get 2
• The switch "6" is turned on and get 32
• The switch "7" is turned on and get 64
• All other switches are turned off
• The sum is 1+2+32+64=99 and this is the resulting address 
• The following picure show the previous addressing process :

4)  Decimal address switches

The detector is given an address by using two switches, the first switch represents ones and the other switch represents tens of the number or address required to be given to the detector .
The switch of ones has 10 positions (0 through 9) .
The switch of tens has either 10 positions (0 through 9) or 16 positions (0 through 15) .
Each switch of them has an indicator which can be turned to get the desired number .

For example, an addressable detector is needed to be given the address 37 , how ??the ones switch  is set to number 7, and the tens switch is set to Number 3, so we get the address 37.
The detector then converts this digital number 37 to the binary number 100101 and sent it as a signal over the wires to the FACP panel .

5) Automatic addressing 

In this method , the FACP panel gives addresses to all of the devices connected on the loops automatically depending on the physical position of each device on the loop.