20 ma output parameters – Rockwell Automation 1440-VST02-01RA XM-120 Eccentricity Module User Manual

Page 63

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Publication GMSI10-UM010C-EN-P - May 2010

Configuration Parameters 55

4-20 mA Output Parameters

The 4-20 mA output parameters define the characteristics of the two 4-20 mA
output signals. The parameters are the same for each output.

Determines whether the relay is failsafe or
non-failsafe.

Failsafe operation means that when in alarm, the
relay contacts are in their "normal," de-energized, or
"shelf-state" positions. In other words, normally
closed relays are closed in alarm, and normally open
relays are open in alarm. With failsafe operation, a
power failure equals an alarm.

The following are true of a relay in failsafe
operation:

The relay is energized when power is applied to
the module.

The relay in a nonalarmed condition has power
applied to the coil.

In alarm condition, power is removed from the
relay coil, causing the relay to change state.

For non-failsafe operation, the following are true:

Under nonalarm conditions, the relay closes the
circuit between the common and the N.C.
(normally closed) terminals.

Under alarm conditions, the relay changes state to
close the circuit between the common and the
N.O. (normally open) terminals.

For failsafe operation, the following are true:

Under nonalarm (with power applied to the unit)
conditions, the relay closes the circuit between the
common and the N.O. terminals.

Under alarm or loss-of-power conditions, the relay
changes state to close the circuit between the
common and the N.C. terminals.

Relay Parameters

Parameter Name

Description

Options/Comments

XM Configuration
Utility

EDS File

Failsafe Relay

Failsafe
Option

XM Configuration
Utility

EDS File

Check means
failsafe

Failsafe

Clear means
non-failsafe

Nonfailsafe

4-20 mA Parameters

Parameter Name

Description

Options/Comments

Enable

Enables/disables the 4-20 mA output.

Min Range

The measured value associated with the 4 mA.

Same measurement unit as the
Eccentricity Unit selection for the
specified channel.

Max Range

The measured value associated with the 20 mA.

XM Configuration
Utility

EDS File

Check to enable

Enabled

Clear to disable

Disabled

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