NI-9477 Getting Started
- Updated2024-02-16
- 3 minute(s) read
NI-9477 Getting Started
NI-9477 Block Diagram
The NI-9477 has sinking outputs. Sinking outputs drive current from DO to COM when the channel is on.
NI-9477 Pinout
Signal | Description |
---|---|
COM | Common reference connection |
DO | Digital output signal connection |
NC | No connection |
Connecting Digital Devices
You can connect a variety of industrial devices, such as solenoids, motors, actuators, relays, and lamps to the NI-9477. You must connect an external power supply to the NI-9477. The power supply provides the current for the output channels.
Ensure that the devices you connect to the NI-9477 are compatible with the output specifications of the NI-9477. Use cables and connectors that are suitably rated for the 20 A module output current limit.
Increasing Current Drive
Each channel of the NI-9477 has a continuous output current of 1 A. If you want to increase the output current to a device, you can connect any number of channels together in parallel.
For example, if you want to drive 4 A of current, connect DO0 through DO3 in parallel, as shown in the following figure. You must turn all parallel channels on and off simultaneously so that the current on any single channel cannot exceed the 1 A rating.
Protecting the Digital Outputs from Flyback Voltages
If the channel is switching an inductive or energy-storing device such as a solenoid, motor, or relay, and the device does not have flyback protection, install an external flyback diode.
Conformal Coating
The NI-9477 is available with conformal coating for additional protection in corrosive and condensing environments, including environments with molds and dust.
In addition to the environmental specifications listed in the NI-9477 Safety, Environmental, and Regulatory Information, the NI-9477 with conformal coating meets the following specification for the device temperature range. To meet this specification, you must follow the appropriate setup requirements for condensing environments. Refer to Conformal Coating and NI RIO Products for more information about conformal coating and the setup requirements for condensing environments.
Operating humidity (IEC 60068-2-30 Test Db) | 80 to 100% RH, condensing |