Indoor single-phase epoxy resin casting current transformer complying with GB/T20840.1/2、IEC61869-1/2 and JB/T8510.1-2007 standards; rated insulation level 31.5/95/185kV, rated frequency 50/60Hz, rated secondary current 5A or 1A. Optional primary current covers 10-2000A; accuracy-class rated outputs range 10-60VA for grades 0.2S,0.5S,0.2,0.5,5P10,5P15,5P20; short-time thermal current ranges 15-100kA, rated dynamic stable current ranges 37.5-200kA; product weight:85kg; ambient operating temperature -5℃~+40℃.
LZZB-27.5 is a 27.5kV indoor epoxy cast current transformer, suitable for medium voltage switchgear applications. It is not for outdoor or high voltage transmission use.
| Parameter | Specification | Verification |
|---|---|---|
| Product Type | Current Transformer | [On Request] |
| Model Code | LZZB-27.5 | Factory nameplate marking |
| Primary Voltage | 10kV | Rated voltage test (IEC 61869-1/3) |
| Secondary Voltage | 5A/1A | Ratio check at rated frequency |
| Accuracy Class | [On Request] | Accuracy test (IEC 61869-2 / IEEE C57.13) |
| Rated Burden | [On Request] | Burden test at rated VA |
| Insulation Type | Dry Epoxy Resin | Dielectric tests per standard |
| Insulation Level (BIL) | 12/42/75kV | Power-frequency & lightning impulse withstand |
| Standards | [On Request] | Certified to listed standards |
| Frequency | 50/60Hz | Per IEC 61869-1 |
| Environment | Ambient: -5℃~+40℃ | Per datasheet limits |
Ideal For
Not Recommended For
Connect primary terminals in series with the line. Secondary terminals are 1S1 and 1S2 for the main winding; if a protection winding is present, use 2S1 and 2S2. Never open-circuit the secondary of a CT while energized - hazardous voltage. Ground the secondary winding at one point. Ensure correct polarity for metering and protection.
Compliant with: [On Request]
S_total = ΣS_instrument + I₂² × (ρ × 2L / A)
Q: What is the insulation level of this CT?
A: The insulation level is 12/42/75kV, meaning 12kV system voltage, 42kV power-frequency withstand, and 75kV lightning impulse withstand.
Q: What secondary currents are available?
A: The secondary current can be 5A or 1A.
Q: What accuracy classes are offered?
A: Accuracy classes include 0.2S, 0.5S, 0.2, 0.5, 5P10, 5P15, and 5P20.
Missing fields are marked [On Request] — never fabricated. M2/M5/M6 verification rows follow IEC 61869 / IEEE C57.13 conventions.
| Rated primary current I1n (A) | Accuracy classCombined | Accuracy class & rated output (VA)COSφ=0.5 | Short-time thermal current Ith (kA/S) | Rated dynamic current Idyn (kA) | Weight (kg) |
|---|---|---|---|---|---|
| 10-50 | 0.2(S)/0.2(S) 0.2(S)/0.5(S) 0.2(S)/5P 0.5(S)/5P | 10 10 15 20 50 30 20 | 150 1in | 375 1in | 85 |
| 75 | 0.2(S)/0.2(S) 0.2(S)/0.5(S) 0.2(S)/5P 0.5(S)/5P | 10 10 15 20 50 30 20 | 15 | 37.5 | 85 |
| 100 | 0.2(S)/0.2(S) 0.2(S)/0.5(S) 0.2(S)/5P 0.5(S)/5P | 10 10 15 20 50 30 20 | 25 | 75 | 85 |
| 150 | 0.2(S)/0.2(S) 0.2(S)/0.5(S) 0.2(S)/5P 0.5(S)/5P | 10 10 15 20 50 30 20 | 31.5 | 80 | 85 |
| 200-250 | 0.2(S)/0.2(S) 0.2(S)/0.5(S) 0.2(S)/5P 0.5(S)/5P | 10 10 15 20 50 30 20 | 45 | 112.5 | 85 |
| 300-500 | 0.2(S)/0.2(S) 0.2(S)/0.5(S) 0.2(S)/5P 0.5(S)/5P | 10 10 15 20 50 30 20 | 50 | 125 | 85 |
| 600-630 | 0.2(S)/0.2(S) 0.2(S)/0.5(S) 0.2(S)/5P 0.5(S)/5P | 10 10 15 20 50 30 20 | 63 | 130 | 85 |
| 750-1000 | 0.2(S)/0.2(S) 0.2(S)/0.5(S) 0.2(S)/5P 0.5(S)/5P | 15 15 20 30 60 40 30 | 80 | 180 | 85 |
| 1200-2000 | 0.2(S)/0.2(S) 0.2(S)/0.5(S) 0.2(S)/5P 0.5(S)/5P | 15 15 20 30 60 40 30 | 100 | 200 | 85 |
Dimension & outline drawing of LZZB-27.5 — click image to zoom / view original.
