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Download PowerFlex 700S Reference Manual - Mid
Transcript
Detailed Drive Operation 2-111 Speed Feedback Loss Ride Through Configuration Parameter 151 [Logic Command] bit 2, "TackLoss Rst" provides a manual switch between primary and alternate speed feedback devices with a “0” to “1” bit transition. A transition from “1” to “0” does not cause a change in operation. Parameter 152 [Applied LogicCmd] bit 2, "TachLoss Rst" shows the status of parameter 151 [Logic Command] bit 2 "TachLoss Rst" switch. Setting parameter 153 [Control Options], bit 16 "Auto Tach Sw" to a value of “1” enables the automatic switching of speed feedback devices when a failure is detected. A value of “0” disables the automatic switching of speed feedback devices. Only automatic switching from the primary device specified in parameter 222 [Mtr Fdbk Sel Pri] to the alternate device specific in parameter 223 [Mtr Fdbk Sel Alt] is available. Switching from the alternate to the primary device must be done manually by setting parameter 151 [Logic Command], bit 2 "TackLoss Rst" from “0” to “1”. Parameter 155 [Logic Status] bit 12, "Tach Loss Sw," shows which speed feedback device is currently active. A value of “0” in bit 12 indicates that the primary speed feedback device selected in [Mtr Fdbk Sel Pri] is active. A value of “1” in bit 12 indicates that the alternate speed feedback device selected in [Mtr Fdbk Sel Alt] is active. Parameter 222 [Mtr Fdbk Sel Pri] selects the primary speed feedback device. It is not intended to use the sensorless selection as the primary (or active) speed feedback device as there is no feedback loss detection used with sensorless operation. Parameter 223 [Mtr Fdbk Sel Alt] selects the alternate speed feedback device. Any selection of feedback devices, including sensorless operation is available providing a corresponding motor type and associated feedback device is present. Settings for parameter 222 [Mtr Fdbk Sel Pri] and parameter 223 [Mtr Fdbk Sel Alt]: 0= 1= 2= Encoder 0 Encoder 1 Sensorless 3 = Reserved 4 = Motor Sim 5 = FB Opt Port0 Parameter 224 [TachSwitch Level] sets the detection level for the automatic speed loss switch over routine. A drop in feedback speed at the percent of rated speed over a 0.5 mSec interval will cause a tach switch from primary to alternate device. Setting this level lower will make the speed detection more sensitive and lower the minimum speed at which a speed switch could occur. Setting this level higher will make the speed switch less sensitive and raise the minimum speed for speed switch detection. Parameter 320 [Exception Event1] bits 2 through 5 show the error status of the corresponding speed feedback device. 2= 3= 4= 5= Encdr0 Loss Encdr1 Loss FB Opt0 Loss FB Opt1 Loss Parameter 365 [Fdbk LsCnfg Pri] and parameter 366 [Fdbk LsCnfg Alt] set the feedback loss configuration for each feedback device. The primary feedback device should be configured to 1 "Alarm". The alternate feedback device should typically be configured to 2 "FltCoastStop".
