AMETEK Lx Series II - Manual (Page 64)

User Manual Lx / Ls Series II
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3.9 Clock and Lock Mode (-LKM/-LKS Option)
Clock and lock mode operation of two Lx or Ls AC power sources is available only if the –LKM
and –LKS options have been installed at the factory. With these options installed, it is possible to
lock an auxiliary unit (-LKS) to a master unit (-LKM). The master unit controls the frequency. This
configuration can be used to create multiphase power systems such as split-phase or six
phases. The auxiliary unit must be set to external clock mode from the Control screen. See
section 4.2.5.
Two BNC connectors are provided on the rear panel of the Lx/Ls for clock and lock mode. Both
need to be connected between the master and auxiliary unit. On the master unit (-LKM), both are
outputs. On the auxiliary unit (-
LKS), both are inputs. Do not connect these BNC‟s between two
master units (- LKM‟s) or damage to the unit could result.
Note: The maximum number of auxiliary units (-LKS) per master (-LKM) is one. No T
connectors are allowed to increase the number of auxiliary units as this may
cause reflections on the clock and lock signals.
Refer to Figure 3-7 for the required connections between the –LKM and –LKS units. The
example is shown for two units, one master, one auxiliary.
WARNING: DO NOT CONNECT THE AC OUTPUTS OF THE –LKM AND –LKS UNITS
TOGETHER. CLOCK AND LOCK OUTPUTS CANNOT BE PARALLELED TO
OBTAIN HIGHER OUTPUT CURRENTS.
Do not use clock and lock mode to obtain higher power capability on the same phase(s). For
higher power configurations, use the multi-chassis configuration through the system interface
connection instead. Refer to section 3.5.3 for multi-chassis configuration and connection
information.
The frequency of the auxiliary unit will track that of the master. The output phase angle of phase
1/A will be locked to the auxiliary unit as well. (See LKM/LKS supplemental specifications for
phase accuracy). This allows split phase or six phase configurations to be created.
3.9.1 Configuration settings
Units configured with the –LKM option will show the Clock as INT (internal) and the mode as
CLK/LOC on the CONTROL screen. Units configured with the –LKS option can be set to INT
(internal) or EXT (external) clock from the CONTROL screen. The MODE setting on the
CONTROL screen of the
–LKS unit determines the power on state for the clock setting. When
set to STAN (Stand-alone operation), the unit powers up with INT clock. When set to CLK/LOC
mode, it powers up in EXT clock mode suitable to clock and lock system operation. See section
4.2.5 for details.
3.9.2 Frequency measurements on –LKS units
Lx or Ls models configured with the –LKS option used in a clock and lock configuration will not
accurately measure frequency if the programmed frequency of the master unit (-LKM) exceeds
2000 Hz unless the frequency setting of the
–LKS is set to the a value close to the programmed
frequency of the –LKM master unit. Setting the –LKS programmed frequency when it is operating
as a clock and lock auxiliary does not affect its actual output frequency as it is controlled by the
–LKM master unit. This provides the controller with the required information to accurately
measure the frequency.