Emerson MC68HC16Z1 user manual Specify Longest Cable Length, Define Alarms as Latched or Unlatched

System and Control Options

6.5.1Specify Longest Cable Length

You may specify the length of the longest cable connected to either of the 4-20mA alarm outputs. The default value is 0-1000 ft. (0-304.8m). Valid entries range from 0-500 ft. (0-152.4m) to 0-5000 ft. (0-1524m), as shown in the Maximum Cable Length screen, below right.

Select the longer cable length installed on either zone. For example, if Zone 1 has 2000 ft. (609.6m) of cable and Zone 2 has 3500 ft. (1066.8m), select 0-4000 ft. (0-1219.2m).

The chosen setting applies to both zones and is correlated to the 4-20mA output of each zone to pro- vide the distance of the leak. Once the range is selected, the following correlation will be applied:

5mA = 0 ft. (0m)

19mA = 4000 ft. (1219.2m)

Table 10 shows the operation of the 4-20mA outputs.

Table 10 Operation of 4-20mA outputs

Signal	Operation
0mA	Indicates cable cannot be monitored
4mA	Indicates normal operation
5mA	0 ft. (0m)
19mA	Longest cable length (ft.)—for example, 4000 ft. (1219.2m)
20mA	Indicates cable fault / contamination

To specify the maximum cable length:

•From the Maximum Cable Length screen, below right, use the arrows ↑↓ to choose the correct range—for example, 0-4000FT(0-1219.2M).

•Press Enter ↵ .

6.5.2Define Relays as Normally Open or Normally Closed

All four digital alarm outputs may be set up as Normally Open (NO) or Normally Closed (NC). The default setting is NO (Normally Open). The chosen setting applies to all cable fault/contamination and leak relays for both zones.

To change the normal state:

•From the Normally Open / Closed screen, below right, use the arrows ↑↓ to choose NO (Normally Open) or NC (Normally Closed).

•For a non-supervised mode, select Normally Open. The relays energize for an alarm condition.

•For a supervised mode, select Normally Closed. The relays de-energize for an alarm condition or loss of power.

•Press Enter ↵ .

6.5.3Define Alarms as Latched or Unlatched

All four digital alarm outputs may be set up as Latched (Y) or Unlatched (N). When configured as Latched, alarms must be manually reset by an operator after they are cleared, as described in 6.9 - Reset Latched Alarms. The default setting is Latched (Y). The chosen set- ting applies to cable fault and leak relays for both zones.

Setup System Menu

SETUP ZN1 ZONE 1

SETUP ZN2 ZONE 2

>SETUP ALARM OUTPUTS

↑↓ =NEXT ↵ =SELECT

SETUP REALARM DELAY SETUP MAPMODE SETUP SYSTEM INFO

Maximum Cable Length

SELECT LONGEST

CABLE CONNECTED

> 0-500FT	(0-152.4 M)
↑↓ =NEXT	↵ =SELECT

0-1000FT (0-304.8M)

0-1500FT (0-472.2M)

0-2000FT (0-609.6M)

0-2500FT (0-762.0M)

0-3000FT (0-914.4M)

0-4000FT(0-1219.2M)

0-5000FT(0-1524.0M)

Normally Open / Closed

ARE LEAK	& FAULT
RELAYS NORMAL OPEN
OR NORMAL CLOSED? NO
↑↓ =NO/NC		↵ =END

To change this setting:

•From the Latched / Unlatched screen, shown at right, use the arrows ↑↓ to choose Y (Latched) or N (Unlatched).

•Press Enter ↵ .

Latched / Unlatched

IS LEAK & FAULT ALARM LATCHED? Y

↑↓ =Y/N ↵ =END

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