Introduction to the C‑TEC CA734 CAST Mini I/O Module and Key Features
The C‑TEC CA734 CAST Mini Input/Output Module is a compact, addressable I/O interface designed for modern fire detection and building management loops. Built for C‑TEC CAST networks, the CA734 pairs a monitored conventional input with a volt‑free changeover relay and an on‑board loop isolator, all inside a small ABS enclosure suitable for surface or panel mounting. It is LPCB and Kiwa Telefication certified to relevant EN54 parts, making it appropriate for many commercial installations where regulatory compliance matters.
Key features at a glance:
- CAST addressable device compatible with C‑TEC XFP/ZFP CAST loops.
- Monitored conventional input configurable as a conventional zone or a monitored normally‑open (NO) switch.
- Volt‑free single‑pole changeover relay rated at 1 A @ 30 V DC (also 0.3 A @ 125 V AC).
- On‑board loop isolator preserves loop integrity in the event of a short circuit.
- Extremely low current draw: typical quiescent ≈ 1 mA, alarm/activation ≈ 7 mA.
- Small footprint (approx. 65 × 65 × 20 mm) for discrete installation.
Detailed specifications and benefits
- Protocol:C‑TEC CAST addressable protocol — native compatibility ensures smooth integration with supported panels.
- Supply voltage:22–40 V DC (some listings show 27–40 V DC — always check panel documentation to confirm supported loop voltage).
- Quiescent and alarm current:Very low quiescent current of approximately 1 mA and alarm current around 7 mA, reducing load on the loop and supporting larger device counts per loop.
- Relay rating:Volt‑free changeover: 1 A @ 30 V DC (also rated for 0.3 A @ 125 V AC) — suitable for signalling circuits, LED drives, or low‑power control tasks.
- Monitored input:Configurable as a conventional zone (supporting roughly 20 detectors + 10 manual call points in typical conventional wiring topologies) or as a monitored NO switch (requiring 470 Ω EOL resistor for monitored switch mode).
- Loop isolator:On‑board isolator fitted to keep the remainder of the loop operational if a short occurs at the device location.
- Dimensions:Approx. 65 × 65 × 20 mm (excl. terminal block & ribbon cable) — compact and unobtrusive.
- Cable length:Ribbon cable approx. 150 mm for easy connection to the loop or backplane.
- Weight:Approx. 47 g — lightweight for simple mounting.
- IP rating:IP40 — suitable for indoor protected environments; additional enclosure or location planning required for harsher conditions.
- Operating temperature:−10 °C to +55 °C — suitable for most internal building environments.
- Enclosure:Small ABS enclosure with 4 mounting tabs for surface or panel installation.
- LPCB:EN54‑17 & EN54‑18.
- Kiwa Telefication:EN54‑13 (loop and I/O unit approvals).
Benefits of these specifications:The CA734 balances low power consumption with useful functionality. The low quiescent current and modest alarm draw help maximise the number of devices supported on a single loop and reduce standby power requirements. The on‑board isolator increases system robustness by keeping the remainder of the loop alive if a local fault arises. The volt‑free relay and monitored input allow integration with a wide range of external devices — from LEDs and sounders to conventional detector zones and third‑party call points.
Use cases and scenarios where the CA734 excels
The CA734 is designed for installers and systems integrators who need a reliable, compact interface between external devices and an addressable CAST loop. Typical applications include:
- Interface for third‑party manual call points:Where a site has existing conventional call points or third‑party devices, the CA734 provides a monitored input and EOL supervision so these devices can be integrated without full detector replacement.
- Small control and signalling tasks:Use the 1 A relay to drive small relays, LEDs, or control inputs on ancillary equipment such as HVAC dampers, door release circuits (subject to local codes), or remote indication panels.
- Retrofit projects:In retrofit scenarios where space behind panels is limited or where surface mounting is preferred, the CA734’s compact enclosure and ribbon cable connection make installation fast and unobtrusive.
- Zone extension for conventional detectors:Configure the monitored input as a conventional zone to bring a small bank of conventional detectors or call points onto the CAST loop.
- Panel‑mounted or distributed installations:The module’s small size and mounting options make it useful for both central panel mounting and decentralised distribution near devices being monitored or controlled.
Comparisons with similar products on the market
When evaluating the CA734, it helps to consider what matters most: certification, size, power consumption, relay rating, and integrated features such as loop isolation and supervised inputs. Compared with other addressable I/O modules in the market, the CA734 typically stands out for:
- Compact footprint:Many I/O modules are larger or require dedicated backbox space; the CA734’s small dimensions make it easier to fit into tight spaces or to surface mount discreetly.
- Low current draw:Its quiescent current of around 1 mA is lower than some alternatives, which is advantageous for maximizing loop capacity.
- On‑board isolator:Not all small I/O modules include an isolator; the CA734’s integral isolator improves loop resilience without adding separate devices.
- Relay capability:The 1 A relay at 30 V DC offers a practical balance for signalling and control tasks; however, installations that require switching of higher currents or mains voltages may need a different module with higher contact ratings or an interface relay.
- Certification:EN54 approvals for loop and I/O performance make it suitable for certified fire systems, a differentiator against generic or uncertified modules.
Limitations to consider: the CA734’s relay is not intended for high‑power switching, and its IP40 rating means it is optimised for protected indoor use. If a project needs weatherproof or high‑current switching, or integration with non‑CAST protocols, alternative modules or external relays should be evaluated.
Customer feedback and installer perspectives
While specific customer reviews vary by project, common feedback themes from installers and system designers include:
- "The CA734 is ideal for retrofits — small, quick to mount and simple to wire with the supplied ribbon cable."
- "Low loop current draw means we can add multiple I/O modules without reconfiguring loop architecture."
- "Integrating third‑party call points to a CAST loop was straightforward using the monitored input configuration."
Installers also appreciate the on‑board loop isolator and the device’s EN54 certifications, which simplify specifying compliant components in regulated installations. For those who needed higher switching capability, installers commonly paired the CA734’s relay output with an external interface relay or contactor as part of the overall solution.
Conclusion: Why the CA734 is a strong choice
The C‑TEC CA734 CAST Mini I/O Module is a well‑balanced, certified I/O interface tailored to the needs of modern addressable loop systems. Its combination of a monitored input, a volt‑free changeover relay, on‑board loop isolation and very low power draw makes it particularly suitable for retrofit work, small control tasks and situations where space is at a premium. With EN54‑17/18 and EN54‑13 certifications and a compact, installer‑friendly design, the CA734 provides a reliable, compliant option for many commercial and institutional projects.
If your installation requires a compact, low‑power, certified I/O interface for CAST loops — especially where supervised inputs and loop resilience are important — the CA734 is a compelling, cost‑effective choice. For full technical setup, wiring diagrams and panel compatibility, always consult the official C‑TEC datasheet and installation manual or contact an authorised distributor.
