Basler Electric BE1-CDS240 Quick Start - Manual (Page 10)

3.) What voltage level is used to develop current flow through the contact sensing inputs?
Voltage level is dependent on the power supply option (BE1-CDS240 style) and the position of
the contact-sensing jumper. See Section 12, Installation, for additional information.
4.) How can the BE1-CDS240 be configured into a simple transformer differential relay?
Two preprogrammed schemes perform this function. One is CDS240-BA87-A-BE from the
BESTCOMS logic library (Basic Differential) and the other is the embedded logic scheme
CDS240-BATX-A-BE (Basic Transformer). See Section 8, Application, for additional
information.
5.) How can the BE1-CDS240 be configured into a generator differential relay?
The BE1-CDS240 can be configured into a generator differential relay by loading the
preprogrammed logic scheme CDS240-BA87-A-BE from the BESTCOMS library. You may
disable the 2nd and 5th harmonic functions by setting these thresholds to zero. See Section 8,
Application, for additional information.
6.) Do I have to connect my current transformers in a special way to compensate for the
phase shift between the high side and low side of a transformer?
No, the BE1-CDS240 can compensate for phase shift. See Section 3, Input and Output
Functions, for additional information.
7.) Should I be concerned about zero-sequence blocking in my CT connections?
No, the BE1-CDS240 can compensate for zero-sequence blocking. See Section 3, Input and
Output Functions, for additional information.
8.) Does the BE1-CDS240 trip output contact latch after a fault?
The answer to the question is Yes and No. In general, once the fault goes away the output
contacts open. The BE1-CDS240 does offer an option to ensure that the contact will stay
closed for at least 200 milliseconds. See Section 3, Input and Output Functions, for additional
information on that function. However, BESTlogic can latch the relay outputs. See Section 8,
Application, Application Tips, for additional information.
9.) A function will not work when I put in settings such as the pickup and time delays.
Make sure that the logic function is enabled.
10.) How many overcurrent elements does the BE1-CDS240 have available?
The BE1-CDS240 has seventeen instantaneous overcurrent and thirteen time overcurrent
elements. Just like any element, each of these elements can be assigned to any output for
building logic equations.
11.) Can I make logic settings at the front panel?
No, the front panel cannot program logic settings. Logic settings must be programmed using
the ASCII command interface or BESTCOMS communication software.
12.) Since the BE1-CDS240 is a programmable device, what are the factory defaults?
The factory default logic is BASIC-87 logic. Default settings are shown with each function in the
instruction manual. For input or output default settings see Section 3, Input and Output
Functions. For protection and control functions, see Section 4, Protection and Control.
2-8 BE1-CDS240 Quick Start 9365200990 Rev M