BY12512d_e.doc / Mai-08
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5.
Change of Phase and Relative Position
The relative phase situation between Master and Slave is normally set by the state upon
power-up or with the last Reset signal (with index modes, the index edges and the programmed
phase displacement define the relative position, see chapter 6.)
During all the operation, this initial phase condition is held without any errors,
unless the operator uses one of the following facilities to change this condition
5.1.
Timer Trimming (Modes 1 - 4 and 8)
This function, activated by the "Trim +" and "Trim -" inputs, provides a temporary higher or
lower slave speed which results in a phase displacement between the motor shafts. When
releasing the trim buttons, the drives will synchronize again in their new relative position. The
differential trim speed is generated by an internal timer and is adjustable. It operates as a
speed addition or a subtraction to the slave, without consideration of the actual absolute
speed. This is why the trim function can also be used at standstill, to move the slave into a
convenient start-up position.
5.2.
Impulse Trimming (Modes 5 and 6)
The ”Trim +” and ”Trim -” inputs accept external pulses from a pulse generator, encoder or a
PLC. Every pulse applied to one of the Trim inputs will shift the phase exactly one encoder
increment forward or backward. This procedure provides repeatable changes and adjustments
of the phase situation between the drives, e.g. under control of an external impulse counter or
a PLC. Modes 5 and 6 can also be used to realize the function of a differential gearbox.
5.3.
Phase Offset Operation (Mode3)
The unit provides an Offset register, which can be set to a desired number of encoder impulses.
Every rising edge at the ”Index Master” input will displace the actual phase forward by the
number of offset impulses, and every rising edge at the ”Index Slave” input will do the same to
the other direction. By this function, the phase situation can be stepped forward or reverse by
the pitch set to the offset register (e.g. in steps of one or several angular degrees).
