Introduction to the CQR SC570 and its key features
The CQR SC570 Surface Magnetic Door Contact is a purpose-built Grade 3 perimeter contact designed for commercial and high-risk intruder alarm installations. Combining a magnetic reed detection element with a mechanical microswitch, selectable end-of-line (EOL) resistors and cover tamper protection, the SC570 provides a flexible, robust solution for doors and frames where reliability and compliance matter. Available in white, anthracite (grey) or brown, and constructed from high-impact polystyrene, the SC570 is rated for 12 Vdc operation with switching current up to 500 mA — an ideal fit where EN50131-2-6 Grade 3 certification is required.
Detailed description of specifications and benefits
The SC570 is engineered to meet the demanding requirements of commercial security systems. Below is a concise list of the product’s key technical specifications, followed by an explanation of what they mean in practice.
- Product codes:SC570/WH/G3/EN; SC570/GY/G3/EN; SC570/BR/G3/EN
- Connections:6 terminals
- Switches:2 (magnet + microswitch)
- Pull-in gap:10 mm
- Contact size:85 x 25 x 21 mm
- Magnet size:85 x 18 x 21 mm
- Contact form:SPST (Form A)
- Contact material:Rhodium
- Voltage:12 Vdc
- Switching current:500 mA @ 12 Vdc
- Material:High-impact polystyrene
- Environmental class:Class II
- Tamper:Cover tamper fitted; optional RFMS
- Standards:EN50131-2-6 (Grade 3)
- Finish / colours:White, Anthracite (Grey), Brown
Benefits explained:
- Grade 3 certification:EN50131-2-6 Grade 3 classification means this device is suitable for high-risk applications such as commercial premises, retail stores, warehouses and other environments where an elevated level of perimeter protection is required.
- Dual switching elements:The combination of a magnetic reed switch and a mechanical microswitch gives installers flexibility for different alarm panel inputs and offers redundancy — if one element fails or is compromised, the other can still provide detection capability.
- Selectable EOL resistors & six-terminal wiring:Multiple terminals and EOL resistor options make the SC570 compatible with a variety of alarm panels and wiring philosophies (including double-pole and double-door configurations). Proper EOL wiring supports supervised circuits and tamper detection to meet system and standard requirements.
- Tamper protection:A fitted cover tamper reduces the likelihood of easy sabotage; for installations requiring radio tamper monitoring or alternate tamper configurations, an optional RFMS tamper is available.
- Rhodium contacts & durable construction:Rhodium-plated contacts improve reliability and reduce the risks of corrosion or contact degradation over time. The high-impact polystyrene housing provides environmental resilience while remaining lightweight and easy to install.
Use cases and scenarios where the SC570 excels
The CQR SC570 is designed for situations where durability, compliance and flexibility are priorities. Typical use cases include:
- Commercial buildings:Offices, multi-tenant buildings and corporate premises often require Grade 3-rated components to meet insurance and security policy requirements. The SC570 provides a certified option for main entrance doors, service doors and secure partitions.
- Retail premises and shopfronts:Retailers needing perimeter monitoring for display entrances, stockroom doors and loading bays benefit from the SC570’s robust tamper and dual-switch design. The selectable EOL resistors enable supervised circuits for early fault detection.
- Warehouses and logistics hubs:High-traffic industrial doors and access points benefit from surface-mounted contacts that are easy to maintain and replace. The 10 mm pull-in gap accommodates typical door tolerances in industrial settings.
- High-risk installations:Sites with elevated threat levels (e.g., server rooms, pharmaceuticals storage, financial institutions) often specify Grade 3 contacts. The SC570’s dual-switch architecture and Grade 3 certification make it suitable for these scenarios.
- Retrofit and new-build projects:The surface-mounted form factor is advantageous for retrofits where recessed wiring is impractical, and the multiple terminal options simplify integration into complex alarm systems during new installations.
Comparisons with similar products on the market
When selecting a perimeter contact, installers and specifiers typically weigh Grade classification, mounting style, switch types, tamper options and wiring flexibility. Here is how the SC570 compares to common alternatives:
Recessed contacts sit inside the door and frame for a discreet profile and reduced exposure to tampering. However, recessed contacts require routing and hole-cutting during installation, increasing labour time and complexity. The SC570’s surface-mounted design trades stealth for faster installation and easier maintenance — a pragmatic choice for retrofits and heavy-duty environments.
Wireless contacts eliminate wiring and provide rapid deployment, but they depend on batteries and radio communications which can introduce maintenance and RF reliability considerations. The SC570’s hardwired, Grade 3 approach provides constant supervised wiring and higher assurance against RF-related vulnerabilities — this is typically preferred where standards or insurance require wired Grade 3 hardware.
Lower-grade surface contacts are suitable for domestic or lower-risk commercial settings and generally cost less. The SC570 is targeted at Grade 3 requirements — it incorporates higher-spec tamper measures, dual switches and supervised wiring capabilities. For sites where risk assessments or insurers mandate Grade 3, the SC570 is the compliant choice.
Installation and practical considerations
Installers should note the SC570’s six-terminal layout and ensure correct end-of-line resistor selection in accordance with the alarm control panel manufacturer and EN50131 guidance. Best practices include isolating power before wiring, testing both the magnetic and microswitch elements, and verifying tamper wiring and supervision. The typical 10 mm pull-in gap eases alignment during mounting, and the offered colour options help match the contact to the door/frame finish.
Conclusion: Why the CQR SC570 is a great choice
The CQR SC570 Surface Magnetic Door Contact offers a balanced mix of compliance, durability and installation flexibility. Its EN50131-2-6 Grade 3 certification makes it appropriate for high-risk and commercial environments that demand certified hardware. The dual-switch design, selectable EOL options and robust materials (including rhodium contacts) deliver both redundancy and long-term reliability. For installers working on retrofits or new builds where supervised wiring, tamper detection and straightforward surface mounting are priorities, the SC570 is a practical, cost-effective choice.
Before ordering, confirm the required approvals (UKCA/CE or regional marks) with your supplier, verify the alarm panel compatibility for double-pole/double-door wiring, and ensure EOL resistor selections are set according to the system specification. With those checks complete, the SC570 stands out as a dependable component for demanding perimeter security projects.
