Johnson Controls Penn VFD68BBB, Технический бюллетень

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VFD68 Variable Frequency Drives
33
0.5–4.5 VDC Ratiometric P499 Transducer
The default parameter values (Table 34 on page 43) on the VFD68 drive are configured to operate a
condenser fan motor on an R410 condensing unit, using a P499RCP-107 or P499RAP-107 ratiometric
transducer (or transducers). Wire one transducer for single circuit condensing systems. Wire two transducers
for dual circuit condensing systems (Figure 23).
The VFD68 has the ability to control motor speed using the higher input signal value of two voltage inputs
when you configure AI1 and AI2 as the same model transducer. For the high-input signal select application
with two transducers (Figure 23 on page 33 or Figure 24 on page 34), use the parameter values in Table 28
and see Adjusting the Default Parameters on page 52.
For high-pressure refrigerants other than R410a, you must calculate and change the C x parameters. For
medium and low pressure refrigerants, you must determine the proper P499R transducer and then calculate
and change the
C x parameters.
For more information, see Setup and Adjustment on page 38 and Parameter Setting Calculations for Motor
Speed vs. Pressure on page 49.
Table 27: Settings for Single or Dual 0.5–4.5 VDC Ratiometric Transducers
Setting Single Transducer Dual Transducer, High-Signal Select
P. 73
1
1. For information on parameters, see Table 34 on page 43.
1 (0–5 V) 1 (0–5 V)
P.266
1 1 (voltage input) 1 (voltage input)
P.267
1 1 (0–5 V) 1 (0–5 V)
Analog Input Terminal AI1 or AI2 AI1 and AI2
AI2 Mode Switch
2
2. See Figure 19 on page 28.
V V
IMPORTANT: If using two input devices, both devices must be identical. Do not use input devices with
different ranges and operating characteristics.
Figure 23: Wiring 0.5–4.5 VDC Ratiometric Input Signal Transducers