Hired-Hand Emergency Back-Up and Alarms: Alert Alarm - Manual (Page 6)

Part No. 4801- 5085 Rev 5-01 Farm Hand Alert Alarm 4
5. General Overview
5.1 Alarm Inputs
The Alert Alarm has seven inputs that can be used to sound an alarm. Three from temperature
sensors, one water quantity, two auxiliaries and one for power out. The water quantity and
temperature sensors can be enabled or disabled. If a sensor is enabled it will be used to generate
an alarm. If a sensor is disabled, it will not generate an alarm, even if the Alert Alarm determines
that its readings are out of limits. The Auxiliary and Power Out inputs are always enabled. The
seven alarm inputs are:
5.1.1 Temperature Sensors #1 ,#2 and #3
The Alert Alarm comes from the factory with three temperature sensors. The Alert Alarm will
trigger an alarm if the temperature goes above the high limit setpoint or below the low limit
setpoint of the sensors. The Alert Alarm will wait 10 seconds after a sensor indicates it is out of
range before triggering an alarm.
5.1.2 Water Quantity Sensor
The Alert Alarm will trigger an alarm if the water quantity goes above the high limit setpoint or if
the water quantity goes below the low limit setpoint. The Alert alarm will wait 60 seconds after
the water quantity limits have been exceeded before triggering an alarm. For low water quantity to
trigger an alarm, there are two other conditions that must be considered as discussed in the next
paragraphs.
Building a Water Flow History
The water quantity meter sends the Alert alarm a pulse of information for every quantity (unit) of
water passing through the meter. The Alert Alarm must measure the time between these pulses to
determine over what period a gallon of water has been used in order to calculate a water flow rate.
For low water quantities, the time between these pulses of information become longer, so the Alert
Alarm must build a history of water usage before making a decision that the low water setpoint has
been crossed. The Alert Alarm needs about 10 minutes of water flow history to make a decision
the low water quantity limit has been exceeded.
Considerations for Growers on Light Programs
If a grower is using an Alert Alarm for measuring water flow in houses that are on Light Programs,
it is possible that the inactivity of the birds (while the lights are out) could reduce the water flow to
levels below the low water setpoint. In these cases the Alert Alarm is equipped to monitor the time
that the lights are out and disable the low limit alarm during these periods. The high water flow
alarm is still active during these “lights out” periods.
Of course, during the lights out period, the Alert Alarm will loose its history record of low water
usage. When the lights do turn back on, the Alert Alarm will begin building its history record that
it needs for triggering a low water alarm. As stated earlier, this will take about 10 minutes.
5.1.3 Auxiliary Inputs #1 and #2
The Alert Alarm is equipped with two auxiliary inputs. These inputs are connected in a closed
loop circuit. On the circuit board located on the door of the alarm enclosure there is a terminal
block for connecting the Auxiliary Inputs (See Section 13.5 for a connection diagram). Each of
the Aux 1 and Aux 2 connections has an IN and OUT terminal. If, at any time, the connection
between the IN and OUT positions is broken (opened), the alarm will sound. There are many
devices on the market that could be used with these inputs. For instance, water pressure switches,
light meters, and thermostats could all be used. Farm Hand controllers could also be used as
illustrated in Section 13.6 . The Alert Alarm will wait 10 seconds after an auxiliary input is broken
before triggering an alarm.