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Example 1: When 4 IRAs are installed
Conditions: Assuming the distance from IRCU/IRCUDAN to IRAs is 50 m. When 5C-2V coaxial cable is
used.
1) Calculating maximum allowable loss of cables
Attenuation from IRCU/IRCUDAN to IRAs
= 2.7 dB × (50 m/100 m) = 1.35 dB
Result is less than maximum allowable loss (15 dB).
2) Calculating maximum allowable voltage drop of cables
Voltage drop from IRCU/IRCUDAN to IRAs
= 3.59 Ω × (50 m/100 m) × 0.09 A
= 0.16 V
Result is less than maximum allowable drop in voltage (3 V).
Use cable lengths that stay within the maximum allowable losses and maximum allowable voltage
drops.
IRA
IRCU/IRCUDAN
50 m
