CLT, CLH, CTT 1, CTRO, CTR, GSK, TZLMA — LV current transformers up to 0.72 kV
Country: Czech Republic · Model: CLT / CLH / CTT 1 / CTRO 1 / CTR 1 / GSK / TZLMA
The seven types of low-voltage current transformers in this line are rated for a maximum voltage of 0.72 kV with a 3 kV test voltage; together they cover primary currents from 25 A to 10 kA with a 5 A or 1 A secondary. They are used for commercial and technical metering in LV switchboards, building main distribution boards and substation switchgear cubicles, and for protecting cable lines against earth faults.
- Umax
- 0.72 kV (test 3 kV); TZLMA — 0.66 kV
- CLT 20
- up to 250 A
- CLH 40.1/40.2/40.3
- 50–1000 A
- CLH 60
- 75–1500 A, continuous 120–160 % In
Technical specifications
| Umax | 0.72 kV (test 3 kV); TZLMA — 0.66 kV |
|---|---|
| CLT 20 | up to 250 A |
| CLH 40.1/40.2/40.3 | 50–1000 A |
| CLH 60 | 75–1500 A, continuous 120–160 % In |
| CTT 1 | 25–600 A |
| CTRO 1 | busbar outdoor, 100–3200 A, 1 or 5 A |
| CTR 1 | summation for protection |
| GSK | with split core, window Ø90–350 mm, 50 A–10 kA |
| TZLMA-1-1 | zero-sequence CT for cable earth-fault protection, 25 A / 1 A, −45…+55 °C |
| Secondary current | 5 A or 1 A |
| Insulation class | E (CLH 60) |
Replacement for
T-0.66, TShP-0.66, TOP-0.66, TShL-0.66, TNSh-0.66 (current transformers 0.66 kV, 5–5000 A); TZLM, TZRL, TZLK (zero-sequence)
selected by purpose and main parameters, please confirm with the manager
Replacement pages: ТНШ-0,66, ТНШ, ТОП-0,66, ТОП, ТШП-0,66, ТШП
Specifications are taken from the manufacturer’s technical documentation. Updated .
Description
The CLT 20 for a primary current up to 250 A is used in indoor switchgear cubicles. The CLH 40 series has three basic versions: CLH 40.1 at 75–800 A, CLH 40.2 at 50–800 A and CLH 40.3 at 50–1000 A. The CLH 60 covers 75–1500 A and holds its accuracy class at 25–100 % of rated burden; its continuous working current is 120 % In, and by agreement 160 % In for 75–1000 A and 140 % In for 1000–1500 A. The active parts of the CLH 60 are placed in plastic housings with insulation of heat resistance class E; the transformer is slip-on, and the number and position of primary buses depend on the rated current. The bushing-type busbar CTRO 1 measures or protects in outdoor switchgear at 100–3200 A, and the busbar summation CTR 1 feeds the protection of indoor devices on the difference of primary currents. The GSK with a split core has a window of 90–350 mm in diameter and a primary current from 50 A to 10 kA; outdoor versions are designated GSK 170–400, indoor ones GSK 100, 120 and others.
How to choose
The model is selected by installation place and primary current. In indoor cubicles up to 250 A the CLT 20 is enough, for 25–600 A the CTT 1 is used, up to 1000 A the CLH 40 series, and up to 1500 A with possible continuous overload the CLH 60. Outdoor devices at 100–3200 A are served by the CTRO 1, and when the buses cannot be dismantled, the split-core GSK is mounted. For protecting the cores of a three-phase cable against earth faults in switchgear up to 0.66 kV, the TZLMA-1-1 with a 25 A primary and 1 A secondary is intended.
Request a price and lead time
CLT, CLH, CTT 1, CTRO, CTR, GSK, TZLMA — LV current transformers up to 0.72 kV. We reply within one business day.
Or email office@usk.ua or call +38 (044) 339-50-20.
FAQ
What are the operating conditions of the TZLMA-1-1 zero-sequence transformer?
Climatic version U (temperate), placement category 2, operating temperature −45…+55 °C, relative humidity up to 100 % at 25 °C. The working position is arbitrary, and the product complies with GOST 12.2.007.0-75.
Can a current transformer be installed without dismantling the buses?
Yes, the split-core GSK with a 90–350 mm window clamps around a live bus or cable for a current from 50 A to 10 kA.
What continuous overload does the CLH 60 current transformer allow?
As standard 120 % In, and by agreement 160 % In for ratings of 75–1000 A and 140 % In for 1000–1500 A.
What is the maximum working voltage of the CLT and CLH current transformers?
The maximum voltage is 0.72 kV with a 3 kV test voltage, and the secondary current is 5 A or 1 A.
Similar products
Isolation Transformer / AutotransformerIsolation Transformer and Autotransformer, isolation transformers and autotransformers
Autotransformer 120/240Autotransformer, 32–100 A
GI 3600 / Isotransformer 2000Isolation transformer, 2–3.6 kVA
Setavolt iSAIndustrial three-phase induction variable transformers 150–800 AREQUEST
Need a price, lead time or replacement?
Send us a request and we will confirm the configuration, lead time and delivery terms. We reply by email.