Macurco OX-6 User Instructions page 8

7. 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.
8. The Fan Relay can be configured for latching or non-latching (default) when activated (when the oxygen concentration drops
below fan relay set point). Once latched in, power will need to be interrupted or the "TEST" button pressed to un-latch the relay
condition.
9. The Fan Relay will engage if the fan setting oxygen concentration drops below the set point 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:

Oxygen concentration has exceeded 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.
10. The Current Loop is 4 mA at 0% v/v, 17.4 mA in clean air (20.9 v/v) and 20 mA at 25% v/v.
Note: Increased levels of oxygen may dramatically increase the flammability of any combustible matter. If oxygen levels rise to
23.5% v/v the Fan Relay and Alarm Relay will be activated. This is a preset function and is not selectable.
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