and the OSCD logic board is faster. In the changes to the microboard the function of the Adaptive
Capacity Board was placed into the microboard, and the ACC board was longer needed in new
production. The new microboard is also compatible with the older designs microboards used in the
OptiView panel. The new OSCD logic also added this new communication port, but also retained all
of the functions required to still communicate with the ACC board.
OptiSpeed and optional harmonic filter logic control boards
Within the enclosure of the VSD model drive, the OSCD logic board and optional Harmonic Filter
logic board are interconnected by a 16-position ribbon cable. This cable provides power for the
Filter logic board and a method of communications between the two boards.
The OSCD Logic board performs numerous functions, control of the OSCD’s cooling fans and
pumps, when to precharge the bus capacitors, and generates the PWM.
The OSCD Logic board also determines shutdown conditions by monitoring the three phases of
motor current, heatsink temperature, baseplate temperature, internal ambient temperature, and
the DC bus voltage.
The optional Harmonic Filter logic board determines when to precharge the harmonic filter power
unit, when to switch the transistors in the harmonic filter power unit, and collects data to determine
power calculations. This board also uses this data to determine shutdown conditions.
Microcomputer control panel VSD related keypad functions
Refer to
160.00-M4
for related keypad functions. Some of the displayed data in this form is different
from the
160.00-M1
. Under the Options Key – the following changes will be displayed:
•
VSD PHASE A INVERTER HEATSINK TEMP = °F.
•
VSD PHASE B INVERTER HEATSINK TEMP = °F.
•
VSD PHASE C INVERTER HEATSINK TEMP = °F.
These three temperature values are replaced with:
•
VSD BASEPLATE TEMP = °F
For the low horsepower model drives. The high horsepower model drives will display three phases
of Baseplate temperature. When the Filter is present, the following data will change from:
•
FILTER HEATSINK TEMP = °F.
This temperature data will now be called:
•
FILTER BASEPLATE TEMP = °F.
The names for the above data were changed because the temperature sensor is now inside the
transistor module instead of the chill plate where the transistor modules are mounted. This new
sensor gives a better indication of true temperature of the power electronics.
OptiView control panel VSD functions
Refer to the specific OptiView™ Control Panel operations manual for detailed information. All of the
OSCD related information is contained under the Motor and Compressor Screens.
VSD adaptive capacity control
The YORK OSCD uses a different approach to speed reduction compared to earlier variable
speed products. There is no longer a pre-programmed surge map – the YORK
®
adaptive system
experiments with the speed and vanes to find the optimum speed for any given condition. It does
not always encounter a surge in the process, but when it does, the Adaptive Capacity Control (ACC)
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Liquid-Cooled OptiSpeed Compressor Speed Drive
