Tyco MX4428 technical manual Ancillary Filtering, Test Modes Summary

Document: LT0273	MX4428 MXP Engineering / Technical Manual
	Device Processing

	AutoReset		Commission		Zone	System		Fast
				Mode	Alarm	test.		Point
					Test	Auto test		Test
						with test
						fire
					Yes	on smoke /	CO
Detector test		No			(Alarm result simulated on 8xxH
applied					ie Heat only detector and on
					ancillary input modules)
FastLogic				Switches	to SmartSense
Filter Divisor	2 on Smoke / CO					1 (bypassed)
	As cfgd on heat
Enhancement		None				None
Step Limit		Bypassed				Bypassed
					As cfgd
					on DIM.
AVF		Bypassed			Bypassed	N/A		Bypassed
					on analog
					detectors
Detector / Anc		Yes			No	No		Yes
LED operates
Circuit / zone	Yes - but				When
	zone			Yes	ALL	No		Yes
goes into
	isolated at				points in
alarm
	FIP				alarm
Point alarm
generates	Yes			Yes	No	No		Yes
event
History high,	No			Yes	No	No		No
low updated
Tracking	No			Yes	No	No		No
updated
FIP CV	Yes			Yes	No	No		No
Updated
Reset				No effect at MXP				Yes
terminates test

Slow Point Test

Yes on smoke / CO.

Simulated 100°C on 8xxH.

Simulated alarm on

ancillaries.

As cfgd As cfgd

None

As cfgd

As cfgd

Yes

Yes

Yes

No

No

Yes

Yes

Normal

No

As cfgd

As cfgd

As cfgd

As cfgd

As cfgd

Yes

When alarm

condition reached

Yes

Yes

Yes

Yes

N/A

Table 9-1 Test Modes Summary

9.22 ANCILLARY FILTERING

If a poll returns the alarm state, then up to 5 immediate re-polls are made. If all these are still in the alarm state then an alarm is generated. If one of the succeeding polls is not in the alarm state, then immediate re-polling stops, but an up-down counter will be retained for the next poll. This counter counts up when an alarm condition is measured, and down when a non-alarm condition is measured. So if there are 5 polls in the alarm state then 1 non alarm the counter will be left at 4. On the next scheduled poll the counter starts from the value it had previously, so only 2 successive polls returning the alarm condition will be required to reach the alarm condition.

The up-down counter always counts up and down (between 0 and 6) depending on whether an alarm condition or not is read from the detector. When the counter reaches 6 a filtered alarm state is generated. When the counter reaches 0 a filtered non-alarm condition is determined. An immediate re-poll is done if the last poll is in the opposite state to the filtered state.

Ancillary faults are filtered in the same way, except that only 4 polls are needed rather than 6, and there is no immediate re-polling, 4 polls 5 seconds apart are required.

Issue 1.5 24 March 2006 Page 9-17