Basler Electric BE1-BPR - Manual (Page 69)

9272000990 Rev J BE1-BPR Functional Description 4-17
CT Current transformer ratio information HMI Menu Branch: N/A
Parameter Parameter Selection Range Increment Default
t P (phase CT)
N (neutral CT)
N/A N/A
CTP=1
CTN=1 ratio pri:sec
or pri/sec
or calculated ratio
1 - 65535 for pri,
sec, and calculated
ratio
1
CT Command
Purpose:
Read or change the current transformer ratio settings.
Syntax: CT[t][=<ratio>]
Comments: An access area 1, 2, or 3 password is required to change settings. The CT ratio can be
entered in three different formats but is always reported as the calculated ratio. The CTP
and CTN values affect the primary current metering values, the contact duty log (DLOG)
calculations, and the COMTRADE fault record current levels.
CT Command Examples:
1. Enter a neutral CT ratio of 400:5.
CTN=80 or CTN=400/5 or CTN=400:5
2. Read the CT ratios.
CT
CTP=50; CTN=80
Three fault detectors, F1, F2, and F3, are provided in the BE1-BPR. Each fault detector can be
configured for phase or neutral current sensing and the type of filtering. Three filtering options are
available: Instantaneous (type 1), Moving Average (type 2), and Instantaneous Three-Phase (type 3).
Fault Detectors
Type 1 Fault Detector. The type 1 fault detector provides high speed operation with a typical pickup time
of one cycle and a typical dropout time of ¼ cycle. Fault detectors F1 and F2 are programmed as Type 1
fault detectors in the preprogrammed logic schemes. Refer to Section 2, Application for a detailed
description of the Type 1 fault detector.
Type 2 Fault Detector. The type 2 fault detector provides a slower but more consistent pickup. This type
of fault detector is appropriate for applications where fault detector sensitivity of less than 0.25 amperes
(relays with 5 A current sensing) is desirable. When a Type 2 fault detector is used, the pickup (PU)
command includes a parameter for entering the number of cycles to be averaged before pickup or
dropout occurs. Refer to Section 2, Application for a detailed description of the Type 2 fault detector.
Type 3 Fault Detector. The type 3 fault detector performance is identical to the type 1 fault detector
except that all three-phase currents must be above the pickup threshold to trigger an output. Refer to
Section 2, Application for a detailed description of the type 3 fault detector.
The LF command configures each fault detector for phase or neutral protection and for high-speed or
moving- average filtering.