99
***Set the CT value that is true for the CT connected to the
ELITE
pro
XC
. Again, because the 2 ½
element method is most often used in high voltage applications, there will be high voltage CTs present.
Use the high-accuracy 5A CT from DENT Instruments on the existing high voltage CT secondary. The CT
value used in the Setup Table should be the primary rating of the high voltage CT (assuming the
secondary output is 5A).
U
SING
T
HE
2-W
ATT
E
LEMENT
(2
C
T
)
M
ETHOD
O
N
A
3-W
IRE
D
ELTA
S
ERVICE
Blondel’s Theorem states that the number of watt elements (CTs) needed to monitor a system is one
less than the number of wires in the system. This means that a 3-Wire Delta service, even though three
phase, requires only two CTs to meter it as there are only three current carrying conductors. The
ELITE
pro
XC
uses the 3 CT method for monitoring Delta services as a default because the data is easier
to interpret. However, if it is required to use only 2 CTs on a Delta such as when it is desirable to use one
ELITE
pro
XC
to monitor two Delta connect loads simultaneously (such as two motors), connect the
meter as shown below.
2 CT, 3-Wire Delta
www.
.com
1.800.561.8187
Содержание ELITEpro XC
Страница 58: ...58 Typical Single Phase 2 Wire Setup Diagram www com information itm com 1 800 561 8187 ...
Страница 59: ...59 Typical Single Phase 3 Wire Setup Diagram www com information itm com 1 800 561 8187 ...
Страница 60: ...60 Typical 3 Phase 3 Wire Delta Setup Diagram www com information itm com 1 800 561 8187 ...
Страница 61: ...61 Typical 3 Phase 4 Wire Wye Setup Diagram www com information itm com 1 800 561 8187 ...