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Hello again,

What is actually EOL, what is the purpose and how does it work. And how to wired it.

Thanks,

Regard

salizam

Guest

EOL means End of Line Resistor These are the resistor values which must be connected to the sensor contact when the Zone shunts are set to the End of Line position, ie away from the terminal block. End of Line Resistors allow Comfort to raise a Trouble alarm when the alarm wiring is cut
You can refer to the installation manual for information on how to connect the resistors.
Comfort\'s End of Line Resistor values are 2.7K ohms in series with the contact and 4.7 K ohms in parallel with the contact.

The 2.7K ohms value can be substituted with 2.2 Kohms without any problem.
The values 2.2 Kohm and 4.7Kohm are commonly used in the UK and some other countries. If Comfort is bneing installed to replace another alarm system with these values, then the EOL resistors need not be changed
Zone Trouble means that the zone shunts are inserted in the \"Double End of Line Position\", but there are NO End-Of Line Resistors connected to the Zone Input.
The Zone shunts are 3 pin headers  marked JZ1 to JZ8 near the terminal block for each zone

Put the shunt Closer to the terminal block for NO End of Line Resistor, and AWAY from the Terminal Block for DOUBLE End of Line Resistors

If you do not install 2 End of line Resistors, then put the shunt  in the position closer to the terminal block

The Installation Manual which explains how to connect zones can be downloaded from https://www.cytech.biz/installation_manual.html The Installation manual is essential to a correct connection.

The Hookup Diagram can be downloaded from https://www.cytech.biz/hookup_diagram.html
A question concerning testing circuits with two end of line resistors.

As I understand it, normally the alarm expects to see 2K7 ohms.
When the sensor is activated it sees 2700 + 4700 or 7400 ohms and raises the alarm type.

What are the tolerances involved? In other words, its not 2700 exactly or 7400 exactly, but some range of values which averages at these.

I ask this because in periodically maintaining the wiring and associated sensor circuits I would like to know when its timely to anticipate problems and tighten up connections / replace sensors on those circuits.

Thanks in advance.
1 K difference should still work
good morning ! 
i just wanna ask how to compute the end of line resistor in fire alarm ?
For comfort, you need 2.2K in series and 4.7 K in parallel

Fire alarms may not be compatible with comfort. most of them are 24V

You need to use 12V smoke or heat detectors for comfort