What Are Low-Current Systems?
Low-current systems (English: Extra Low Voltage / ELV systems) are the general name for all electrical systems that operate at low voltage and low current below 48 V DC or 50 V AC and meet buildings’ security, communication, control, and automation needs. Unlike strong (power) currents, they do not distribute electricity directly; they are used for transmitting information, data, audio, video, and signals. They include systems such as fire detection, security cameras (CCTV), card access, data cabling (Cat6/Cat6A/fiber), public address/music broadcasting, intercom, nurse call, automatic barriers, and building automation. In modern buildings, low-current investment accounts for 15–30% of the total electrical budget and is critical for comfort, safety, and efficiency.
Types of Low-Current Systems
1. Fire Detection and Alarm System
A life-saving system that detects a fire using smoke/heat/flame detectors, triggers an alarm, and activates the evacuation warning system when necessary.
- Conventional system: Zone-based, for small buildings
- Addressable system: Identifies each detector individually (preferred)
- Standard: TS EN 54, TS CEN/TS 54-14
- Brands: Notifier, Honeywell, Bosch, Hochiki, Mavili
2. Security Camera (CCTV) System
A video security system used for monitoring and recording.
- IP camera: 2 MP – 12 MP, PoE-powered, remote access
- Analog (HD-CVI/AHD) camera: For locations with existing cabling
- NVR/DVR: 4–128 channel recording, 7–90 days of storage
- Brands: Hikvision, Dahua, Axis, Bosch, Hanwha
3. Card Access and Access Control
A system that regulates authorized personnel entry and keeps records.
- RFID card, fingerprint, facial recognition, mobile NFC
- Turnstile, door control, parking barrier
- Integration with PDKS (Personnel Attendance Control)
- Brands: ZKTeco, Suprema, HID, Paxton
4. Data Infrastructure and Structured Cabling
The backbone for computer, telephone, camera, and server connections.
- Cat6 / Cat6A / Cat7 copper cabling
- OS2 / OM4 / OM5 fiber optic cabling
- TIA/EIA-568 and ISO/IEC 11801 standards
- Rack cabinet, patch panel, switch, AP
5. Public Address and Music Broadcasting System
A system that provides announcements, music, and emergency evacuation announcements throughout the building.
- Zoned speaker lines
- Voice Alarm (TS EN 54-16): Certified for emergency evacuation
- Brands: Bosch, TOA, Inter-M
6. Intercom and Building Door Phone
An audio and video communication system for inside and outside the apartment.
- IP intercom (remote viewing, mobile connectivity)
- 2-wire system (for older buildings)
- Brands: Comelit, 2N, Akuvox
7. Nurse Call System
Provides patient-staff communication in hospitals, nursing homes, and healthcare facilities.
- TS EN 50134 compliant
- Bedside, bathroom, corridor lamp
8. Building Automation (BMS)
Manages lighting, HVAC, elevators, energy, and security systems from a single center.
- KNX, BACnet, Modbus, LonWorks protocols
- Schneider EcoStruxure, Siemens Desigo, Honeywell Niagara
Low-Current System Installation Process
- Needs analysis and risk assessment
- System design: AutoCAD topology, equipment list, cable takeoff
- Authorized company and certificate verification (authorization certificate required for fire systems)
- Cable pulling and infrastructure: Ducting, tray, conduit system
- Equipment installation: Detector, camera, card reader, switch
- Programming and commissioning: Addressing, software configuration
- Testing, training, and handover: Commissioning acceptance test, user training, documentation
- Periodic maintenance agreement: Legally mandatory once a year for fire systems
Legal Requirement for Fire Detection Systems
In Turkey, under the Regulation on the Fire Protection of Buildings, a fire detection system is mandatory in the following buildings:
- Residential buildings over 51 m and with a total area over 2,000 m²
- All hospitals, hotels, shopping malls, schools, and nursery/kindergarten buildings
- Industrial facilities containing hazardous materials
- All structures stipulated in the building inspection report
DOA Enerji Low-Current Services
DOA Enerji Aydınlatma provides turnkey installation for fire detection, CCTV, card access, data cabling, public address, intercom, and building automation systems. For fire detection, we have an engineering staff authorized by Civil Defense; for CCTV, our experts are Hikvision/Dahua certified; and for data infrastructure, we have an AMP/Panduit/Legrand certified cabling team. A 2-year warranty and annual periodic maintenance service are offered on all projects.
Frequently Asked Questions (FAQ)
What is low current, and how is it different from strong current?
Low current is used for transmitting signals/data/sine waves below 48 V DC or 50 V AC (camera, alarm, data). Strong current distributes electrical energy at 220–400 V LV or 6–36 kV MV (outlets, motors, lighting). Routing channels must be physically separated as required by regulations.
How much does a low-current system cost?
With 2026 prices, a basic package (fire + CCTV + data + card access) for a 500 m² office is ~250,000–400,000 TL, and for a 5,000 m² shopping mall ~1,500,000–3,500,000 TL. The cost varies by system variety, number of cameras/detectors, brand, and cable length.
Should I choose an IP camera or analog for CCTV?
For new installations, IP cameras are recommended; they offer higher resolution (4–12 MP), PoE power (single cable), remote access, and analytics features. In facilities with existing coaxial cabling, HD-CVI / AHD analog cameras provide an economical solution.
Is maintenance mandatory for fire detection systems?
Yes. Under TS CEN/TS 54-14 and the Civil Defense regulation, periodic maintenance and testing must be performed at least once a year by an authorized company. Detector cleaning, battery checks, signal tests, and system function checks must be recorded.
Can a card access system integrate with PDKS?
Yes. Modern card access systems (ZKTeco, Suprema, Paxton) can work integrated with PDKS (Personnel Attendance Control System). They can provide SGK-compliant outputs, shift calculations, leave tracking, and overtime reports. With Cloud PDKS modules, remote branches can be managed from a single center.