Troubleshooting E52 Fault - Hitachi P1 Basic Instruction Manual

TR OUB LE S HO O TIN G E 5 2 F AU L T
WHAT IS AN E52 FAULT - An E52 fault is a speed devia�on fault. The encoder detected speed deviated from the output
commanded set-frequency.
HOW IS AN E52 FAULT DETERMINED – When the VFD is opera�ng in closed loop vector control only (AA121 = 10) the VFD is
constantly comparing the detected frequency from the encoder to the commanded frequency while running. If the detected
frequency from the encoder deviates outside of the allowable value bb-83 for the allowable �me bb-84 then a speed devia�on is
determined to have occurred.
• Check the encoder sha� collar is �ght on the sha� and the encoder tether is secure.
• If the encoder was replaced in the field be sure to check for correct encoder signal phasing. Try switching sig A with sig B.
• If the fault is occurring at start you will need to determine if the encoder is working. To do this remove the encoder from
the motor sha� and navigate to VFD parameter dA-20 the current posi�on monitor. With the encoder in your hand rotate
the encoder sha� and see if the pulse count is changing either coun�ng up or coun�ng down. You can also navigate to VFD
parameter dA-08 and rotate the encoder sha� and see if there is any frequency being detected.
• If a load is stuck in the air, you can change the VFD control mode to open loop SLV AA121 = 08 for the purpose of lowering
the load. DO NOT keep using the hoist in open loop mode if it is a closed loop hoist since the safety protec�ons will be
disabled.
• If this fault is occurring at random check to make sure the motor brake circuit is not dropping out randomly. Check to see if
the encoder signal in unstable by using dA-08 detected speed monitor, this value while run should be close to the set-
frequency value. The allowable tolerance for dA-08 is + / - 1.5hz from the commanded frequency.
• Contact Detroit Hoist for further assistance.
12/17/2018 Hitachi P1 Closed Loop Hoist Basic Instruc�on Manual Firmware V19 – V25 19