Tandem Hoist Ezcom (Speed / Command / Status Syncing) - Hitachi P1 Basic Instruction Manual

TANDEM HOIST EZCOM (SPEED / COMMAND / STATUS SYNCING)

Tandem hoist EZCOM can be used when 2 hoists are used in tandem operation and require the frequency, hook limit status,
command status, and fault status to sync between each hoist.
The VFD's will need to be configured to communicate between each other and the internal logic activated. A 2-wire shielded cable is
required to connect between the VFD's SN/SP RS485 terminals (Belden 9538 type cable is recommended). Typically, A/B relays will be
used to supply an input to the VFD to activate the syncing logic when in tandem mode, digital input 6 is typically used.
HOW IT WORKS – The VFD's use the SN/SP RS485 terminals to send frequency, drive status, and command status Modbus registers
values between each other. While in sync mode the VFD's compare the directional commands based on conditional internal logic,
which ensures if a hoist reaches a limit, or loses a command signal the opposite hoist will follow the command. While in tandem mode
the VFD's also compare frequency values and always sync to which VFD has the lowest frequency value, this ensures the set
frequencies always match.
NOTE – If the VFD's are configured for EZCOM tandem sync (UE-43 > 0) and the EZCOM communication is disconnected _______ (db-
08 = 9999) the hoists will ignore all directional commands even when in individual mode and the communication disconnection must
be addressed. The only exception is if a brake slip is detected the VFD will ignore the EZCOM communication disconnection and
operated in an individual mode configuration.
TROUBLESHOOTING EZCOM COMMUNICATION DISCONNECTION (db-08 = 9999) – Use the VFD monitor parameter db-08 to monitor
the EZCOM communication disconnection. If the value shown in db-08 = 9999 then the communication is disconnected or timed out
or not configured correctly. Check the wiring between the VFD's SN & SP terminals. Also make sure the VFD's power up at the exact
same time or use a digital input to active the EZCOM communication by configuring one of the available digital inputs to 098:ECOM if
power cannot be verified at the same time. Verify EZCOM parameters are configured correctly using the EZCOM parameter chart on
the next page.
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