MSA MultiGard 5000, Manual

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3103-1001 Rev. 0
5. Common Alarming
Four outputs (alarm, warning, trouble and horn) are provided for common alarming. The function of
these relays is to indicate the Alarm Status of the MultiGard 5000 System. The alarm status of each
line per sensor is indicated in the Status column of each of the Gas Levels and Alarming Status
display screens (see section 4.1.2).
Dual MultiGard 5000 Systems
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On the dual MultiGard 5000 Systems there are two sets of four outputs; one set for System A and the
other set for System B. Functionality is identical except as noted later in this section.
5.1 Alarm
The alarm set point per sensor per point can be entered in the Set Points display screen (see section
4.2.3). The alarm relay may be configured as fail-safe (normally energized) or non-fail safe (normally
de-energized) in the Common Alarming Set-up display screen (see section 4.2.12).
Exceeding an alarm level will cause the MultiGard 5000 unit to indicate an alarm level, alter the
state of the alarm relay and energize the horn relay. The Acknowledge Horn button on the overview
screen will promptly de-energize the horn relay. Once a latched alarm has cleared, the Condition
Acknowledge button can be used to return the unit to the normal operating state.
5.2 Warning
The warning set point per sensor per point can be entered in the Set Points display screen (see section
4.2.3). The warning relay may be configured as fail-safe (normally energized) or non-fail safe
(normally de-energized) in the Common Alarming Set-up display screen (see section 4.2.12).
Exceeding a warning level will cause the MultiGard 5000 System to indicate a warning level, alter
the state of the warning relay and pulse the horn relay at a 50% duty cycle (2 sec. energized, 2 sec.
de-energized). The Acknowledge Horn button on the overview screen will promptly de-energize the
horn relay and inhibit the pulsing action. Once a latched warning has cleared, the Condition
Acknowledge button can be used to return the unit to the normal operating state.
5.3 Trouble
The trouble set point is used to detect below scale sensor drift and its value can be entered per
sensor per point in the Set Points display screen (see section 4.2.3). The Trouble relay is always
configured to be fail-safe (normally energized) and may not be changed. Exceeding a trouble level
will cause the MultiGard 5000 System to indicate a trouble, de-energize the trouble relay and pulse
the horn relay at a 20% duty cycle (1 sec. energized, 4 sec. de-energized). The Acknowledge Horn
button on the overview screen will promptly de-energize the horn relay and inhibit the pulsing
action.
The Condition Acknowledge button can be used to return the unit to the normal operating state once