PAGE 7 12-5-97 CHAPTER 1: INTRODUCTION
6.1 Network Power Consumption
6.1.1
Each option card requires a maximum of 95mA @ 11VDC of DeviceNet
network power for the
transceiver circuit. Input voltage range is from 11VDC to 24VDC
7.1 Response times (@500K baud):
Poll response
< 1mS (consume 4 byte/produce 12 byte)
Explicit response
Typical
< 500uS
Maximum
< 400mS (Inverter parameter access)
8.1 Connections:
Produced
Consumed
Explicit message:
20 bytes (maximum)
24 bytes (maximum)
Poll message:
12 bytes (expandable to 14) 4 bytes (expandable to 8)
9.1 Configuration:
9.1.1
The Card is configurable locally through the drive keypad or remotely through the network.The
EDS file is provided for DeviceNet
configuration programs such as DeviceNet
Manager.
10.1 Introduction to DeviceNet
10.1.1
DeviceNet™ is a high-speed twisted pair + power pair + Shield network primarily used to
retrieve low level I/O data. In addition to accessing I/O, the network can be used to configure and modify
operation of a remote node. By conforming to the DeviceNet
specification, low-level devices from
multiple venders can co-exist on the same network and be accessed from the same high- level device.
10.1.2
A DeviceNet
network can support up to 64 nodes on a single network. Baud rates of 125, 250
and 500kbaud can be selected, based on the total span of the network. The network is typically
configured in a Trunkline-dropline, which allows node removal without terminating the network.
10.1.3
Typical DeviceNet
installations require a high-level device or master to access the data from
low-level devices. Low-level devices, which simply control local hardware, are usually Group-2-Only
Server devices. A Group-2-Only-Server device provides the protocol services of the Predefined
Master/Slave Connection Set. While DeviceNet
provides many connections and services, the
Predefined Master/Slave Connection Set provides a limited and known subset of services which are
sufficient and simple to access through most DeviceNet
Scanners. The Master is high-level device,
which is used to establish communication, initiate communication and transfer data with the low-level
slave devices. A scanner is a type of master which is used to access data from a slave device in real-
time. However, other masters may also exist such as a device which is used as a low-level device
configuration tool (i.e. DeviceNet
Manager). A low-
level device which supports Group-2-Only-Server services can only be connected to one master at a time.
10.1.4
The typical connections provided by a Group-2-Server-Only devices are Explicit, Polled and
Strobed. An Explicit connection is typically considered a low priority connection, which provides access
to all the device’s parameters accessible over the network. An Explicit connection is also required to start
both the Polled and Bit-Strobed connections. A Polled connection is a higher priority and high-speed
connection that moves small amounts of I/O data on a consistent basis. A Bit-Strobed connection is a
higher priority connection that broadcasts control information in one packet for all low-level devices on the
network. The HE300DNT100 only supports the Explicit and Polled connections.
