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Control Mode

You can change the control mode by selecting Control Mode from the Mode menu or press

the Hot Key and select Control Mode.

Control Mode lets you define where the instrument receives its set point. Follow the prompts

on the handheld communicator display to choose one of the following control modes: Analog

or Digital.

Choose Analog if the instrument is to receive its set point over the 4 to 20 mA loop. Normally,

the instrument control mode is Analog.

Choose Digital if the instrument is to receive its set point digitally, via the HART

communications link.

A third mode, Test, is also displayed. Normally, the instrument should not be in the Test

mode. The handheld communicator automatically switches to this mode whenever it needs to

stroke the valve, for example during calibration or stroke valve. However, if you abort from a

procedure where the instrument is in the Test mode, it may remain in this mode. To take the

instrument out of the Test mode, select Control Mode then select either Analog or Digital.

Detailed Setup

The DVC2000 digital valve controller has the capability to communicate via the HART

protocol. This section describes the advanced features that can be accessed with a handheld

communicator. Table 3 lists the default settings for a standard factory configuration. Table 4

provides the actuator information required to setup and calibrate the instrument.

Instrument Mode

You can change the instrument mode by selecting Instrument Mode from the Mode menu or

press the Hot Key and select Instrument Mode.

Instrument Mode allows you to either take the instrument Out Of Service or place it In Service.

Taking the instrument Out Of Service allows you to perform instrument calibration and also

allows you to change setup variables that affect control, provided the calibration/configuration

protection is properly set. See Setting Protection.

Terminology

Instrument Level – There are four (4) levels of functionality available: AC, HC, AD and PD.

AC – This level provides the capability to setup and calibrate the positioner through the local

user interface or a handheld communicator.

HC – This level provides additional capability for advanced configuration of the positioner

(such as travel limits/cutoffs, custom characterization and minimum open/closing time).

Also, information is available through the HART protocol for diagnostic alerts such as travel

deviation, cycle count and travel accumulation.

AD – This level provides advanced diagnostic capabilities for performance testing. When used

with ValveLink software, instrument health can be evaluated with tests such as Valve Signature,

step response and dynamic error band. The software program provides detailed analysis

with graphics.

PD – This level provides automated, non-intrusive testing of the operating performance of

the control valve assembly. When used with ValveLink software, tests to isolate component

degradation can be run on the valve assembly without affecting the process.

Local Interface – The DVC2000 comes standard with a Liquid Crystal Display (LCD) and four (4)

pushbuttons. The local interface provides the capability to setup and calibrate the positioner

and view basic diagnostic messages.

Magnet Assembly – This is the feedback component that is mounted directly to the valve stem.

It supplies a magnetic field that is sensed by the digital valve controller.

Options Board – The DVC2000 digital valve controller is available with two (2) limit switches

and a valve position transmitter. The options board includes the additional circuitry and

terminations that are required to support these output signals.

Pole Piece – Inserted into the DVC2000 housing and protruding through the back of the

instrument is a two-pronged fork that houses the magnetic sensor for position feedback.

Instrument Description

The DVC2000 digital valve controller is a communicating, microprocessor-based

current-to-pneumatic valve positioner. It is designed to replace standard pneumatic and

electro-pneumatic valve positioners.

In addition to the traditional function of converting an input current signal (4 to 20 mA) to a

pneumatic output pressure, the DVC2000 digital valve controller communicates via a local

display panel and/or via the HART® protocol. An option is available which provides isolated

circuitry for two (2) integrated limit switches (for open/close valve indication) and a valve

position transmitter (for separate valve position feedback).

Magnet Assembly – This is the feedback component that is mounted directly to the valve stem.

It supplies a magnetic field that is sensed by the digital valve controller.

Options Board – The DVC2000 digital valve controller is available with two (2) limit switches

and a valve position transmitter. The options board includes the additional circuitry and

terminations that are required to support these output signals.

Pole Piece – Inserted into the DVC2000 housing and protruding through the back of the

instrument is a two-pronged fork that houses the magnetic sensor for position feedback.

Measuring range

Range: Continuously adjustable via configuration software

Vrms (metric) = 5 – 100 mm/s (±25 to ±500 µm)

Vrms (Imperial) = 0.197 in/sec to 3.937 in/sec (±0.984 mils to ±19.685 mils)

Frequency range: 10 – 1000 Hz (VDI 2056. DIN 4566. ISO 3945)

Selectable frequency ranges: 5 – 50 Hz, 10 – 50 Hz, 50 – 1000 Hz, or 50 – 1600 Hz

Lift coil current: 0 – 8 mA, adjustable in 40 μA steps

Lift coil current accuracy: ±0.5% of full scale range, ±0.5% of set value

Maximum allowable load: 3.4 kΩ at 2 mA

Minimum dynamic input voltage: 311 mV peak to peak

Maximum dynamic input voltage: 9500 mV peak to peak

Sensor power supply:

Individually buffered sensor power supply

Galvanically isolated from all system voltages and system supply voltages.

Protected against open and short circuits

Features:

• Dual-channel, 3U-sized, 1-slot plug-in module that cuts cabinet space

requirements in half compared to traditional four-channel 6U cards

• API 670-compliant hot-swappable modules

• Remotely selectable limit multiplication and trip bypass

• Pre- and post-buffered and proportional outputs, 0/4-20 mA outputs, 0 – 10 V outputs

• Use with electric (electromechanical) sensors 9266. 9267. or 9268

Sensor Inputs

Number of inputs: two independent channels

Input Type: Electro-mechanical, Differential

Emerson sensor inputs: Part No. 9266. 9267. or 9268

Isolation: Galvanically isolated from power supply

Input resistance: >100 kΩ

Input voltage range: – 5 – +15 VDC

Input frequency range:

Lower cut-off frequency 1 or 5 Hz

Upper cut-off frequency 50 – 2000 Hz adjustable