Description
BTT-30B current transformer block
BTT-30B is an aircraft current transformer block used in the differential-protection channel of a 30 kVA alternating-current generator and its feeder during single-generator operation. It belongs to the protection equipment of the aircraft electrical system. The block does not switch or regulate the generator by itself; it supplies the protection circuit with a current-related signal so an internal generator or feeder fault can be distinguished from normal load current.
Full descriptionCollapse description
Role in generator differential protection
Aircraft electrical-system descriptions identify BTT assemblies as groups of three current transformers, one for each phase. The protection compares the monitored currents on the generator and feeder sides. A significant imbalance indicates a fault inside the protected zone and is processed by the associated protection-and-control equipment. BTT-30B must therefore be checked as part of the complete generator channel.
Recorded electrical data
The existing technical record specifies a rated primary current of 83.5 A at 208 V and 400 Hz. At this current and frequency, the recorded average rectified output is 3.4–4.1 V. These values belong to BTT-30B and were retained without borrowing the smaller dimensions or different output range of BTT-30BT. Supply and test connections must follow the product passport.
Construction and related blocks
Recorded dimensions are 170 × 109 × 96 mm and mass is not more than 2 kg. The related BTT-30BT, BTT-40B and BTT-40BT blocks serve similar protection functions but have different ratings, construction or installation positions. They are useful cross-references and are not automatic substitutes.
Inspection and ordering
Inspect the body, phase conductors or terminals, mounting points, connector contacts, insulation and data plate. Bench checking must reproduce the approved primary-current and load conditions. When ordering, specify BTT-30B exactly, the generator type and rating, aircraft or electrical-system execution, quantity, condition and required passport. Other generator-control equipment is listed under Electronic Control Units.
Technical details
- Product Name
- Current Transformer Block
- Primary Designation
- BTT-30B
- Original Cyrillic Designation
- БТТ-30Б
- Product Type
- Three-phase aircraft current-transformer block
- Function
- Differential current protection of an AC generator and its feeder
All specificationsCollapse specifications
- Generator Rating
- 30 kVA
- Operating Arrangement
- Single-generator operation
- Rated System Voltage
- 208 V AC
- Rated Frequency
- 400 Hz
- Rated Primary Current
- 83.5 A
- Average Rectified Output
- 3.4–4.1 V at the specified primary current and 400 Hz
- Dimensions
- 170 × 109 × 96 mm
- Mass
- Not more than 2 kg
- Alternative Designations
- BTT-30B; BTT30B; БТТ-30Б; БТТ30Б
- Interchangeability
- Not automatic with BTT-30BT, BTT-40B or BTT-40BT
- Documentation
- Product passport and aircraft generator-protection documentation
Payment & delivery
Orders ship from our hub in Dubai. Partner stock is first transferred to Dubai, then shipped to you.
Dubai stock: 100% before dispatch. Partner stock (Remote stock) and Pre-order: 50% advance payment to start the order and 50% before shipment from Dubai to you.
Availability, lead time, delivery cost and payment terms are confirmed for your order before payment.
Payment & delivery terms