84-40 9424200996
Settings Calculation Examples BE1-11m
Figure 84-50. User Programmable Alarms Screen
Navigate to Alarm Configuration, Alarms, and enable Programmable Alarm 1 as a non-latching minor
alarm as shown in Figure 84-51. This alarm will show in the sequence of events and alarm reporting as
“Unbalance Alarm”.
Figure 84-50 and Figure 84-51 also show the Differential Alarm programmed at the end of the Current
Differential (87) subsection.
Figure 84-51. Alarm Settings Screen
50-5 - Overload Protection
The 50-5 element is used for overload protection while the motor is running. This protection is configured
according to the service factor of the motor. The pickup setting should be 115-125 percent of the service
factor per IEEE C37.96-2000, IEEE Guide for AC Motor Protection. If the service factor is 1.0, then
overload pickup should be 115% of FLA. The pickup setting should be 130 percent of FLA for a service
factor of 1.15. (If the service factor is unknown, use 1.0.)
In this example, the service factor is 1.15 and the pickup setting is calculated using Equation 84-32.
=
1
1.30 = 205
1
60
1.30 = 4.44
Equation 84-32. 50-5 Pickup
A delay prevents the BE1-11m from operating for temporary overloads while the motor is running.
Typically, the delay is set short, but can be set longer if the process is significant or if an operator is
regulating the load. The NEMA MG-1 standard states that a large motor can withstand an occasional
overload of 1.5 • FLA for 30 seconds. A conservative time delay (using a factor of 1) is calculated in
Equation 84-34. The hot safe stall time is found in the motor manufacturer data.
= 1
(
8.5
)
= 8.5
Equation 84-33. 50-5 Time Delay
Select three-phase mode, set the Pickup setting to 4.44 Secondary A, and set the Time Delay to 8.5
seconds as shown in Figure 84-18.
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