Color Coded Solid Core Current Transformers
Solid core Current Transformers (CTs) look like donuts with wires attached. These ring-shaped devices slip over the power lines and measure the electrical current flowing through the line. The CT "secondary" wires connect to the meter, facilitating power and energy calculations.
Solid core CTs are very accurate (0.3% maximum error), small in size, and inexpensive. However, power must be turned off and the circuit opened, generally at a circuit breaker, so that the solid core CT can be slipped over the power line. After installation the power wire must be reconnected to close the electrical circuit. Installation usually only takes a minute or two per CT.
Specification
Dimensions
| A | B | C (Max.) | D1 | |
|---|---|---|---|---|
| Inches | 0.72 | 2.06 | 0.82 | 48.00 |
| Millimeters | 18.3 | 52.3 | 20.8 | 1219.2 |
1Standard lead length. Dimension tolerance ± 0.10" unless otherwise noted. Use approved for lead lengths up to 500 ft. at rated accuracy. Lead wires are UL1015, 18 AWG, rated at 600 volts.
Electrical Characteristics
For safety considerations, an open circuit protection feature is provided by an internal bi-directional 6.8 volt TVS.
| Current (Max.) | Ratio | Ratio Err | Phase Err | Burden Resistor | BIL |
|---|---|---|---|---|---|
| 220 Amps | 200:0.1 | < 0.1% | < 6' | 21 Ohms Max. | 10 KV |
Physical Characteristics
Each current transformer is color coded for ease of installation: Colored lead wires (Black, Red, Blue, White/Black, White/Red or White/Blue) always connect to X1 at the meter. The white leads always connect to X2. The white case half identifies the H1 side, which faces the incoming line. Refer to meter hookup diagrams for more information. See figure 1.
| Model Numbers | Phase Color | Description |
|---|---|---|
| CT200148BKSO-0.72 | Black (L1) | 200 AMP current transformer |
| CT200148RDSO-0.72 | Red (L2) | 200 AMP current transformer |
| CT200148BLSO-0.72 | Blue (L3) | 200 AMP current transformer |