Basler Electric BE1-11m - Manual (Page 544)

532 9424200996 Rev L
Instantaneous Undercurrent (37) - Loss of Load Protection
The 37 element protects the motor from overheating by tripping when a load or shaft coupling is lost and
motor current drops. The 37 element protects only when the motor is in running mode and can be set to
trip on a loss of load condition, especially for pump motors where flowing water cools the motor. For
pumps, a loss of current would indicate less cooling. The pickup setting is calculated in Equation 53.
𝑃𝑖𝑐𝑘𝑢𝑝 = 75% 𝑜𝑓 𝐹𝐿𝐴
𝑆𝑒𝑐𝑜𝑛𝑑𝑎𝑟𝑦
= 0.75 ∙ 4.54 = 3.405 𝐴 𝑠𝑒𝑐𝑜𝑛𝑑𝑎𝑟𝑦
Equation 53. 37 Pickup
Select three-phase mode, set the pickup setting to 3.405 A, and set the time delay to 100 ms as shown in
Figure 360.
Figure 360. Protection, Current, Instantaneous Undercurrent (37) Screen
Protection - Voltage
Two undervoltage protection elements are used to monitor undervoltage conditions.
Undervoltage (27P-1)
When the motor is running, undervoltage conditions can jeopardize production (motor speed) or affect
electronic or digital controls. When running voltage dips occur, the motor should be disconnected quickly.
Set the 27P-1 protection element active in running mode only for 90 percent per the NEMA MG-1
standard. A delay of 100 ms will ride through fast voltage transients and prevent false tripping. The pickup
setting is calculated in Equation 54.
𝑃𝑖𝑐𝑘𝑢𝑝 = 90% ∙ 𝑁𝑜𝑚𝑖𝑛𝑎𝑙 𝑉𝑜𝑙𝑡𝑎𝑔𝑒 = 0.90 ∙ 120 = 108 𝑉 𝑠𝑒𝑐𝑜𝑛𝑑𝑎𝑟𝑦
Equation 54. 27P-1 Pickup
Select Three of Three mode, set the Pickup setting to 108 V, and set the Time Delay to 100 ms as shown
in Figure 361.
Settings Calculation Examples BE1-11m