Basler Electric BE1-11m - Manual (Page 566)

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Figure 388. 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 69.
𝑃𝑖𝑐𝑘𝑢𝑝 = 𝐹𝐿𝐴 ∙
1
𝐶𝑇𝑅
∙ 1.30 = 205 𝐴 ∙
1
60
∙ 1.30 = 4.44 𝐴 𝑠𝑒𝑐𝑜𝑛𝑑𝑎𝑟𝑦
Equation 69. 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 71. The hot safe stall time is found in the motor manufacturer data.
𝑇𝑖𝑚𝑒 𝐷𝑒𝑙𝑎𝑦 = 1 ∙ 𝐻𝑜𝑡 𝑆𝑎𝑓𝑒 𝑆𝑡𝑎𝑙𝑙 𝑇𝑖𝑚𝑒 (8.5 𝑠) = 8.5 𝑠𝑒𝑐𝑜𝑛𝑑𝑠
Equation 70. 50-5 Time Delay
Select three-phase mode, set the Pickup setting to 4.44 A, and set the Time Delay to 8.5 seconds as
shown in Figure 355.
Figure 389. Protection, Current, Instantaneous Overcurrent (50-5) Screen
Instantaneous Overcurrent (50-6) - Jam Protection
The 50-6 element is used for jam protection while the motor is running. It protects the motor when the
load torque exceeds the torque capability of the motor. This condition develops motor current equal to or
approaching locked-rotor current, and reduces terminal voltage depending upon the motor impedance.
Settings Calculation Examples BE1-11m