Allen-Bradley 1407-CGCM-DLR, Руководство пользователя, Страница: 59 / 268

Rockwell Automation Publication 1407-UM002B-EN-P - February 2019 59
CGCM-DLR Unit Operation Chapter 3
Protection Functions
The CGCM-DLR unit detects the fault conditions that are listed and described
in the following section. Faults that are detected by the CGCM-DLR unit are
communicated to the host Logix programmable controller. Fault flags are
communicated in the Scheduled Read table. A fault flag is latched until the host
controller resets it. The host Logix controller can reset all CGCM-DLR unit
faults by setting the tag FltReset = 1 once the fault condition is cleared.
The CGCM-DLR unit automatically shuts down excitation if one of these faults
occurs:
•
Overexcitation voltage
•
Reverse VAR
•
Logix controller fault
Fault conditions can also be configured to activate the CGCM-DLR unit fault
relay output. Once configured, the CGCM-DLR unit fault relay operates
independently of the host Logix controller program (including Controller
Run/Program mode).
See Chapter 4 for information on how to configure the fault relay operation.
CGCM-DLR Protection Capabilities
The protective functions in the CGCM-DLR unit are time-proven and designed
to provide a high degree of reliability, repeatability, longevity, and accuracy. The
CGCM-DLR unit is designed to meet or exceed applicable CE standards, but
was not tested to all standards that many North American utilities use to define
utility grade protection. However, the CGCM-DLR unit does possess many of
the features that define utility grade protection.
The CGCM-DLR unit can be used as primary protection in applications that do
not require utility grade protection. The unit can be used in utility applications
where the authority having jurisdiction has approved the CGCM-DLR unit for
use as primary protection. In applications that require utility grade protection,
where the local authority has not evaluated or approved the CGCM-DLR unit,
the CGCM-DLR unit can be used for secondary protection with a primary
protection system.
Loss of Excitation Current (40)
The CGCM-DLR unit activates this fault when excitation current that is
metered by the CGCM-DLR unit falls below the user specified loss of excitation
current setpoint for more than the user-defined delay time. In a redundant
CGCM-DLR unit system, excitation is disabled and a transfer to the secondary
controller occurs. If this fault occurs, tag
LossExcFlt
= 1 in the Scheduled Read
table. This fault is inhibited during voltage build and when soft start is active.