National Instruments FieldPoint FP-1300, Руководство пользователя, Страница: 30 / 53

Chapter 2 Installing and Configuring Hardware and Software
FP-1300 User Manual 2-18 ni.com
Terminating the CAN Network
If you connect the FP-1300 to a multiple-node CAN network that is already
terminated, refer to the
Powering the FieldPoint System section. If you
connect the FP-1300 to a single-node CAN network, you need to terminate
the network. To terminate the CAN network, complete the following steps:
1. Install a 120
Ω
resistor between the CAN_H and CAN_L terminals on
the FP-1300.
2. Install another 120
Ω
resistor at the other end of the CAN cable
between the CAN_H and CAN_L terminals.
After you have terminated the CAN network, verify that the total resistance
between CAN_H and CAN_L is 60
Ω.
Powering the FieldPoint System
Each FP-1300 on the network requires an 11–30 VDC power supply. The
FP-1300 filters and regulates this supplied power and provides power for
all the I/O modules in the bank. Therefore, you do not need to provide
power separately to each FieldPoint I/O module in the bank.
Calculating Power for a FieldPoint Bank
The power requirements for a FieldPoint bank that uses an FP-1300
network module are calculated as follows:
Power = 1 W + 1.1
× Σ
(I/O Module Consumption)
This is the amount of power the FP-1300 network module consumes from
the power supply to power itself and the I/O modules. It does not include
any power consumed by devices that you wire to the terminal bases. The
CAN bus requires a separate power supply.
The FP-1300 supplies 9 W of power to the I/O modules. Using I/O modules
that consume more than 1 W can reduce the total number of I/O modules
allowed in the bank to less than nine. Refer to the operating instructions for
each I/O module for power consumption information.