BECKWITH ELECTRIC M-2601, Instruction Book

Page: 45 / 70

4–6
M-2601/02/03 Instruction Book
4.7 Ratio Multipliers
VT User Correction Voltage
This feature is included to permit VOLTAGE
TRANSFORMER ratio correction. It permits the
measured voltage to be adjusted over a
K
12 V
ac range to compensate for voltage transformer
ratios that would yield an improper representation
of customer voltage.
CT User Correction Multiplier
This feature is included to permit CURRENT
TRANSFORMER ratio correction. It permits the
measured voltage to be adjusted over a 50 to
200% range to compensate for current transformer
ratios that would yield an improper representation
of customer voltage.
Primary Voltage and Current Multipliers
Primary quantities are displayed when voltage and
current multipliers are set into the control. The
voltage multiplier is: V
mult
= V
pri
/(V
sec
+
(V
sec
)(V
corr
)). For example: If the VT ratio is
7620/120 = 63.5 and the correction multiplier is
+5.8%, the ratio of the voltage multiplier is 60.
The current multiplier is the value of the line CT
primary rating divided by 0.2 A.
For a CT primary rating of 1000 A, the multiplier
is:
CT
mult
= 1000/0.2 = 5000
The current multiplier setting range is
from 20 to 25,000 in increments of 1.
4.8 Tap Position
The Autodaptive
®
Regulator Control applies to
tapchanger designs with a lowest tap position
configuration of –16 to a highest tap position
configuration of +16.
Tap Position by Keep Track
This feature allows the control to keep track of
the presently operating tap.
It is recommended that the indicated tap position
be compared to the mechanical tap position
indicator at regular intervals, and that the indicated
value be corrected, if necessary.
The user initializes the control at a given, known,
tap position upon installation by performing the
following steps:
1. Determine the actual tap position from the
external tap position indicator on the
regulator.
2. Using the SLIMcom™ communications
program, calibrate the tap position by
entering the current tap value under "tap
position". The tap position is now calibrated
to recognize all subsequent operations so
as to “keep-track” of the present tap
position.
3. The present tap position is indicated in
the Tap Position screen.
The keep-track procedure recognizes tapchanges
commanded via:
• The control software.
• The panel switches.
• External contacts.
The tap position stored in memory is not affected
by a loss of supply power.