KYORITSU 6310 Instruction Manual - Manual (Page 138)

5.4 VT/ CT KEW6310
5.9
KEW6310
5.4 Using supplementary VT/CT’s (not supplied with the instrument)
DANGER
● Never make measurement on a circuit in which electrical potential exceeds AC600V.
● Connect the Power cord to a socket outlet. Never connect it to the socket outlet of AC240V or more
.
● This instrument must be used on the secondary side of VT(transformer) and CT(current transformer).
● Do not open-circuit the secondary side of a supplementary CT while it is energized because of the high
voltage generated at the secondary side terminals.
CAUTION
● When a VT or CT is used the measurement accuracy is not guaranteed due to several factors namely
phase characteristics and VT/CT accuracies.
The use of supplementary VT/CT’s may be required if the voltage/current values of the circuit under test fall
outside the instrument measuring range. In this case the value at the primary side of circuit can be obtained
directly by measuring the secondary side with appropriate a VT or CT installed in the line under test as follows.
< Example of single-phase 2-wire (1ch) “1P2W x 1” >
When rating of the secondary side of CT is 5A, use of Clamp sensor 8128 (50A type) and
testing at 5A Range is recommended.
In this case, set the actual ratio of VT and CT to be used.
* VT ratio: see “Section 4“
* CT ratio: see “Section 4“
VN V1 A1
N
L
Source Load
VT CT
i