Baker Hughes Panametrics AquaTrans AT600, Руководство пользователя

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Chapter 3. Wiring the AT600 electronics
24 AquaTrans™ AT600 User’s manual
3.5 Wiring the analog output for HART communication
The standard configuration of the model AT600 flow meter includes one isolated 0/4-20mA analog output.
Connections to this output may be made with standard twisted-pair wiring. The current loop impedance for this
circuit must not exceed 600 ohms.
Figure 27: Analog output/HART communication wiring
To wire the analog output, refer to Figure 27 on page 24 and complete the following steps:
1. Verify that the main power has been disconnected from the unit, and then open the enclosure.
2. Install the required cable gland in the chosen gland hole on the bottom of the enclosure.
3. Refer to Figure 23 on page 19 for the location of terminal block I/O, and wire the terminal block as shown above.
4. Secure the cable clamp.
Note the following:
• The standard analog output port provides only a 0/4-20mA analog output. If the HART communication option is
desired, it must be specified at the time of purchase.
• The AT600 analog output is an active mode type, with power provided internally by the meter. Do not connect
an external 24V power supply to this circuit.
• Prior to use, the analog output must be set up and calibrated (see “Inputs/outputs” on page 41).
• When in meter is in configuration mode, the analog output is locked at 3.6 mA. After exiting from configuration
mode, the meter will resume normal operation.
3.6 Wiring the Modbus communication
The optional AT600 Modbus port is a two-wire, half-duplex RS485 interface. If this option was specified at the time of
purchase, proceed with the wiring instructions below.
To wire the Modbus RS485 serial port, refer to Figure 23 on page 19 above and complete the following steps:
1. Verify that the main power has been disconnected from the unit, and then open the enclosure.
2. Install the required cable clamp in the chosen gland hole on the side of the electronics enclosure.
3. Route one end of the cable through the gland hole and wire it to terminal block.
4. Secure the cable clamp.
WARNING!
Always be sure to disconnect the main power supply from the AT600 before proceeding
with these instructions.
WARNING!
Always be sure to disconnect the main power supply from the AT600 before proceeding
with these instructions.
Model AT600
PIN: 0
PIN: 1
HART master/
ampere meter
Load
(maximum
600 ohms)
Volts +
(int. pwr. sup.)
Volts -
(common)