Johnson Controls YORK YVAM 0350, Operation & Maintenance Manual

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The OSCD can now be configured for many different input voltage levels. Lower input voltages may
de-rate the input power rating of the OSCD, but the OSCD will produce the same output voltage
and will use the same motor.
The Harmonic filter is no longer an option, and the function of the Harmonic filter is included in
a new rectifier module. This type of arrangement for the rectifier no longer requires a separate
power unit for the Harmonic filter. Also, this rectifier is part of the power unit for the inverter, which
reduces the number of parts required and increases reliability.
The new OSCD control system allows for high speed operation of the compressor motor. This
improvement eliminates the need for a gear system between the compressor motor and the
compressor. Without a gear system, reliability and efficiency are improved.
The new power unit consists of a newly designed bus capacitor, new light weight plastic cooling
blocks, new power module gate driver design, new rectifier module, and the cooling system is
connected to the front of the power unit for reduce down time and service cost.
The new Bus capacitor is the core of the power unit. The new capacitor is made of a material that is
much more robust and has a longer lifetime than Bus capacitors commonly used in the past. Also,
the capacitor case contains the mounting studs required to mount all of the other components of
the power unit.
The Harmonic filter operation is now part of the input to the OSCD. This feature is no longer an
option when this OSCD is used with the YVAM chiller.
New special plastic cooling blocks were designed for this OSCD. These plastic cooling blocks provide
a light weight solution by replacing heavy copper or aluminum cooling blocks, while providing
direct liquid cooling for the rectifier and inverter power modules. They also provide a method for
mounting the power module assemblies to the bus capacitor within the power unit.
The power unit contains components needed for the output of the OSCD in a highly integrated and
modular design. On top of the bus capacitor is the laminated bus structure. This structure connects
the rectifier, bus capacitor, and the inverter to each other. The 0490B drive has a gate driver power
supply board located on top of the laminated bus structure. The rectifier and inverter assemblies
are attached to each side of the bus capacitor. The rectifier and inverter assemblies each contain
two power modules for each phase, with each assembly containing a total of six modules. Each
gate driver board controls two power modules, and plugs into the power module. The gate driver
power supply board, gate driver boards, rectifier, and inverter can all be replaced as individual
parts. This reduces the cost and down time for field repairs.
Ease of maintenance is provided by using the communications link between the chiller control
panel and the OSCD. The cooling pumps and fans can be turned on from the chiller control
panel. This provides for a safer coolant changes. The programmed chiller full load amps is also
programmed from the chiller control panel.
Smart Sensor System (SSS) is a system that assists the high ambient temperature fault in the
detection of rapidly rising temperatures.
As with chiller systems such as the YCIV and YVAA, the drive has a NEMA 4 outdoor enclosure
rating. The drive also contains an internal heater to ensure components are not damaged due to
extreme cool.
Smart sensor system
The smart sensor system provides an early detection of localized overheating due to loose high
power electrical connections, or components that have not raised the ambient temperature of
the enclosure to the drive's ambient temperature fault level. When smart sensors detects a fault,
a signal is sent to the smart sensor board. The smart sensor board then commands the circuit
breaker to open through the circuit breaker's shunt trip.
YVAM Control Center 112