Daikin VRV Reference Manual page 9

Diversity & Connection Ratio - What's the Difference?
Connection Ratio:
Both indoor & outdoor units have a Capacity Index number
¡
(e.g. FXMQ30PBVJU indoor unit & RXYQ192TTJU outdoor unit)
Total sum of IDU
index numbers
This ratio is defined as a percentage:
¡
Example: 8 x FXMQ30P connected to 1 x RXYQ192T =
–
240 / 192 = 1.25
Therefore the Connection Ratio =
–
System Diversity:
DIVERSITY is the difference between the Maximum System
Load demand and the Maximum Capacity of the outdoor unit,
at design conditions
The VRVXpress tool can define diversity - also as a percentage
¡
Example: 8 x FXMQ30P connected to 1 x RXYQ168T
Maximum Load required at any given time:
–
Maximum Capacity of the ODU at design conditions:
–
VRV defines the DIVERSITY of the system at:
–
In this example, if the maximum load is called for, the outdoor unit
¡
will fall short of demand by 3,954btu – This VRV design has a
2% system diversity
To summarize: Connection Ratio does NOT indicate the diversity
of a VRV system. Use of the VRVXpress selection tool will
indicate clearly if selected equipment has a system diversity
or not.
÷
ODU index
number
=
CONNECTION
RATIO
125%
..............170,269 btu
.....166,315 btu
..........................-2%
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