Channel types

To specify the location and type of channel associated with the field measurement, you configure the channel or port type and the Device Signal Tag (DST) of the IO_IN or IO_OUT parameter. The following channel types are available.

Table: Channel types for I/O cards and CHARMs
I/O	Channel or port types	Description	Function block use
Analog Input card and Analog Input CHARM	Analog Input Channel	Reports the analog value present at the channel. Analog Input CHARMs configured as a 0-20 mA CHARM do not support open loop detection.	Used with AI and PID function blocks as input I/O references. Used with AO and PID function blocks as readback references to read a 4 to 20 mA signal. The AI CHARM can also read a 0 to 20 mA signal.
Analog Input card and Analog Input CHARM	HART Analog Input Channel	Reports the analog value present at the channel and up to four digital values from a HART field device.	Used with AI and PID function blocks as input I/O references. Used with AI and PID function blocks as readback references to read a 4 to 20 mA signal.
Serial card	RS232 port RS422/485 half duplex port RS422/485 full duplex port	Reports the serial value present at the port. Protocol can be RTU or ASCII. Baud rate options range from 300 to 115,200.	Used with AI and PID function blocks as input I/O references.
Analog Output card and Analog Output CHARM	Analog Output Channel	Drives the output to an analog value written by the controller and holds the output at that value.	Used with AO and PID function blocks as output I/O references when driving a 4 to 20 mA signal. The AO CHARM can drive a 0 to 20 mA signal as well as a 4 to 20 mA signal. The 0 to 20 mA signal does not support HART.
Analog Output card and Analog Output CHARM	HART Analog Output Channel	Drives the output to an analog value written by the controller and holds the output at that value. This channel type also sends HART commands to gather as many as eight dynamic variables and four device variables from a HART field device.	Used with the AO function block as output I/O references. Used with AO and Alarm Detection function blocks as readback references to read dynamic and device variables. The 8 dynamic variables are used in AI function blocks.
Discrete Input card and Discrete Input CHARM	Discrete Input Channel	Reports the discrete value present at the channel.	Used with DI and Device Control function blocks as input I/O references when reading a discrete (On/Off) signal. Used with DO function blocks as a readback I/O reference for a discrete signal.
Discrete Input card and Discrete Input CHARM	Pulse Count Input Channel	Reports the number of discrete pulses detected at the channel. For pre-Series 2 cards: maximum input frequency for pulses is 125 Hz. For Series 2 cards: maximum input frequency for pulses is 75 Hz. For DI CHARMs: maximum input frequency for pulses is 10 kHz.	Used with AI and PID function blocks as input I/O references to read a pulse count.
Discrete Output card and Discrete Output CHARM	Discrete Output Channel	Drives the output to a discrete value written by the controller and holds the output at that value. Outputs immediately reflect the output value that was received. Upon receiving a configuration that indicates a change from one type of output to another, the outputs switch to the off state.	Used with DO and Device Control function blocks as output I/O references when driving as discrete signal.
	Momentary Output Channel	Produces a momentary pulse by driving the output active for a specified time period each time the controller writes a value of TRUE (1, On). Upon receiving a new pulse value, the existing pulse is allowed to terminate normally before the new value is written. Upon receiving a configuration that indicates a change from one type of output to another, the outputs switch to the off state.	Used with DO and Device Control function blocks as output I/O references to output a fixed-duration pulse whenever the block writes a TRUE (1) value to the channel.
	Continuous Pulse Output Channel	Produces a continuous pulse by driving the channel output value ON for a percentage of the specified time period. Upon receiving a new on-time value (which is a percent of the pulse period), the output of the channel stays on for that amount of time and goes to the OFF state for the remainder of the pulse period. At that time the channel receives a new on-time value from the module.	Used with AO and PID function blocks as output I/O references when driving an actuator requiring discrete pulse input.
Isolated Input card	Thermocouple	Reports the temperature of the thermocouple and is Cold Junction Compensated.	Used with AI function blocks as input I/O references.
	Uncharacterized thermocouple	Reports the absolute value of the voltage at the screw terminals, and that voltage is uncompensated for the local cold junction temperature.	Used with AI function blocks as input I/O references.
	RTD, ohms	Reports the temperature of the RTD bulb.	Used with AI function blocks as input I/O references.
	Resistance	Reports the ohms of the measured element.	Used with AI function blocks as input I/O references.
	mV	Reports the value of the millivolts at the screw terminals.	Used with AI function blocks as input I/O references.
	Voltage	Reports the value of the voltage at the screw terminals.	Used with AI function blocks as input I/O references.
RTD, ohms card and RTD / Resistance Input CHARM	RTD Channel	Reports the temperature of the RTD bulb.	Used with AI function blocks as input I/O references.
	Resistance Channel	Reports the ohms of the measured element.	Used with AI function blocks as input I/O references.
	User	Reports the temperature of the RTD bulb.	Used with AI function blocks as input I/O references.
SOE card (Sequence of Events)	Discrete Input Channel	Reports the discrete value present at the channel.	Used with DI and Device Control function blocks as input I/O references when reading a discrete (On/Off) signal. Used with DO function blocks as a readback I/O reference for a discrete signal.
SOE card (Sequence of Events)	SOE Discrete Input Channel	Reports the discrete value present at the channel and captures up to 32 process-upset events per card and sends the events to a specified workstation.	Used with DI and Device Control function blocks as input I/O references when reading a discrete (On/Off) signal. Used with DO function blocks as a readback I/O reference for a discrete signal.
Thermocouple, mV⁽¹⁾ card and Thermocouple / mV Input CHARM	Thermocouple	Reports the temperature of the thermocouple and is cold junction compensated. This card does not support open loop detection.	Used with AI function blocks as input I/O references.
Thermocouple, mV⁽¹⁾ card and Thermocouple / mV Input CHARM	Uncharacterized Thermocouple	Reports the absolute value of the voltage at the screw terminals, and that voltage is uncompensated for temperature (for example, mV input).	Used with AI function blocks as input I/O references.
Multifunction card/Pulse Count Input card	DI or Pulse Input (PIN) Channel	Reports the number of discrete pulses or peaks of a sine wave detected at the channel. Maximum input frequency is 50KHz.	Used with the Pulse Input function block to read the FREQUENCY parameter of a DST from a pulse input channel.
Multifunction card/Pulse Count Input card	DI or Pulse Input (PIN) Channel for pulse input gating	Channel 1 can be used as an external trigger to enable or disable the capture of pulses on channels 2, 3, and 4. To enable the capture of pulses, use DeltaV Explorer to set the ENABLE_PI_GATING card-level parameter to True. Define channel 1 as DI and channels 2, 3 and 4 as PI. The card status will be Bad if ENABLE_PI_GATING is True, but the channels are not defined correctly.	Used with the Pulse Input function block to read the FREQUENCY parameter of a DST from a pulse input channel.
AS-Interface card	2 ports	Each port functions as an AS-Interface master. The AS-Interface master controls communications on the network by polling the slave devices, issuing commands, and receiving and processing replies from the slave devices. Supports autosensing and auto-addressing of devices.	Same as Discrete Input, and Discrete Output cards.
H1 fieldbus card	2 ports	Functions as the Link Active Scheduler (LAS) and manages the transmission of messages across a fieldbus segment. Each port connects to one fieldbus segment. Up to 16 devices are supported for each segment.	Supports up to 64 fieldbus function blocks.
DeviceNet card	one port	Supports polled communication as the DeviceNet master and acts as the interface between the DeviceNet network and the DeltaV system. Supports up to 61 slave devices and supports the online addition of devices.	Same as Analog Input, Analog Output, Discrete Input, and Discrete Output cards.
Profibus DP card	one port	Functions as the Profibus DP master and acts as the interface between the Profibus DP network and the DeltaV system. Supports up to 64 slave devices and supports the online addition of devices.	Same as Analog Input, Analog Output, Discrete Input, and Discrete Output cards.

⁽¹⁾ When the Thermocouple, mV card is plugged into a Thermocouple terminal block, it functions as a Thermocouple card. When it plugs into an I/O terminal block, it functions as an mV card.