Macurco TX-12-HS Instructions D'utilisation page 9

4. The dry contact, SPDT fan relay has three terminals. The common (COM.), normally open (N.O.) and the normally closed
(N.C.) contact. The fan relay can switch up to 5.0 A up to 240 VAC. See OPERATION section of these User Instructions for
details on relay settings.
5. The Fan Relay can be configured for latching or non-latching (default) when activated (when the gas concentration exceeds fan
relay set point).
6. The Fan Relay will engage if the fan setting Hydrogen Sulfide concentration is exceeded for longer than the Fan Relay Delay
time. Unless it is configured for latching, the fan relay will disengage once both of these conditions have been met:

Hydrogen Sulfide concentration has dropped below fan setting

Fan Relay Run time has been exceeded
Note that the "disable" fan setting will cause the fan relay to not engage. The fan relay will engage in trouble fault condition (if
the Trouble Fan Setting Option is set to "ON") and will disengage once trouble fault condition is cleared.
7. The Current Loop is 4 mA in clean air and 20 mA for 50 ppm Hydrogen Sulfide
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