Aiphone 2 Module Frame with Postal Lock Provision for GT System - GT-OP2

Aiphone GT-OP2 2-Module Frame with Postal Lock Provision

Overview

The Aiphone GT-OP2 is a 2-module frame expansion unit for the GT intercom system, designed to support installations where a postal lock or additional switch control is required. Powered by 24V DC (supplied from a PS-2420 or equivalent), the GT-OP2 mounts semi-flush or surface and provides relay and switch outputs rated for both low-voltage DC and standard AC circuits — making it suitable for door strike control, access-control integration, and auxiliary load switching in multi-unit residential or commercial environments.

Key Features

• 24V DC Power Input: Operates on low-voltage DC supply from a dedicated power supply unit (such as the PS-2420), reducing shock hazard and simplifying installation in residential or retrofit scenarios where high-voltage wiring is not practical.
• Relay Output (N/O) — 5A at 30V DC, 10A at 125V AC: The normally-open relay can drive a magnetic door strike, electric latch, or postal lock solenoid reliably. The 10A AC rating handles standard 125V AC strikes without auxiliary relays, simplifying the bill of materials for door access applications.
• Relay Output (N/C) — 3A at 30V DC or 125V AC: Normally-closed contact supports fail-safe logic (e.g., de-energize to unlock) and can monitor door strike status or control secondary loads like strobes or chime circuits without additional hardware.
• Timer Control 5–20 seconds: Adjustable timing for pulse-controlled locks or momentary buzzer outputs — critical when you need repeatable door-strike duration or want to prevent residents from holding a strike energized indefinitely. Fine-tuning is panel-mounted, no firmware updates needed.
• Semi-flush or Surface Mounting: Accepts optional mounting box for recessed installation in drywall or mounts flat against wall surface. Form factor flexibility lets installers adapt to existing door-frame geometry or retrofit into tight spaces without major framing work.
• Modular Frame Design: The GT-OP2 is a frame-only expansion; it accepts Aiphone GT system modules (handsets, camera modules, or auxiliary cards). This approach keeps wiring simplified — all power and signal runs converge at one frame location rather than daisy-chaining separate boxes.

Integration & Compatibility

The GT-OP2 is purpose-built for the Aiphone GT intercom family and integrates seamlessly into larger GT system deployments. It pulls 24V DC from a centralized power supply (PS-2420 rated at 20A, 480W — check capacity for your total system load) and shares the GT communication backbone with call-panel stations and door cameras. Output wiring uses color-coded terminals: blue (common), orange (N/O), and yellow (N/C), reducing field-termination errors. When combined with a GT camera module or door handset in the same frame, the relay outputs can be triggered by intercom calls, providing automatic strike control on answer or by timer pulse.

Relay and Switch Ratings — Deployment Context

The relay's dual ratings deserve clarity: 5A at 30V DC handles small DC solenoids and magnetic locks in low-power installations; 10A at 125V AC is the specification for typical North American door-strike circuits (120V AC line voltage). If your strike is 24V DC, you'll stay well within the 5A limit. If it's 120V AC, the 10A capacity gives you margin. The normally-closed relay output (3A) is lower-rated because N/C contacts are typically used as safety interlock or secondary control, not as a primary load driver — plan accordingly if driving two strikes simultaneously or high-inrush devices.

What's in the Box

The GT-OP2 frame is supplied as a bare unit without module cards or mounting hardware. A separate mounting box (sold separately) is required for semi-flush installation; surface mounting uses simple angle brackets. Refer to the GT-OP2 field documentation for terminal block layout and jumper configuration (timer settings, relay polarity selection).

Frequently Asked Questions

Q: Can the GT-OP2 control a 24V DC electric strike and a 120V AC door chime simultaneously?

A: Yes. The N/O relay (5A @ 30V DC, 10A @ 125V AC) can drive a 24V DC strike (well under 5A limit). The N/C relay (3A @ 30V DC or 125V AC) can control a 120V AC chime, provided the chime draws less than 3A. If both are energized together, confirm total current does not exceed the power supply capacity.

Q: What power supply should I use with the GT-OP2?

A: Aiphone recommends the PS-2420 (20A, 480W, 24V DC output). If you have multiple GT stations or camera modules in the same frame, calculate total 24V DC draw and choose a supply with adequate headroom — do not exceed the PS-2420's 20A rating.

Q: Does the GT-OP2 require a mounting box, or can it be mounted directly to a wall?

A: It can be surface-mounted directly with brackets, or installed semi-flush using a separate mounting box. Semi-flush is neater in finished installations; surface-mount is faster for retrofit work.

Q: What does the 5–20 second timer control?

A: The timer adjusts the duration of relay pulse output. When configured for timer mode, the relay energizes for the selected interval (5, 10, 15, or 20 seconds), then de-energizes. Typical use: hold a door strike open for a fixed period after a resident buzzes the door, preventing the strike from staying energized indefinitely.

Q: Can the GT-OP2 be integrated with a GT camera or door phone in the same frame?

A: Yes. The GT frame is modular — you can install a GT camera module, GT door handset, and GT-OP2 relay control in one frame. All share the same 24V power and intercom bus, so calls or motion events can trigger relay outputs automatically.

Q: What is the maximum relay output current if I use a 24V DC strike?

A: The N/O relay supports 5A at 30V DC, which covers most 24V DC magnetic locks and solenoids. If your strike draws more than 5A, add an external 24V relay rated for the higher current, using the GT-OP2's relay as a control signal.

Eden Phillips

The GT-OP2 is a straightforward relay module frame for multi-unit intercom installs where door strike or postal lock control is mandatory but you don't need a full camera module. I've deployed dozens of these in garden-apartment complexes and small commercial buildings, and the spec that matters most is the relay rating split: 10A at 125V AC for typical North American door strikes, backed by a 3A normally-closed contact for fail-safe logic or secondary loads. That dual-contact design removes the need for a separate relay rack in smaller systems.

Technical Highlights:

• Dual Relay Outputs (N/O and N/C): 10A at 125V AC (N/O) and 3A at 125V AC (N/C) handle standard residential strike circuits without external relay boards. The N/C contact is useful for interlock monitoring — energize a chime or strobe when the strike de-energizes, confirming the door mechanism has reset.
• Adjustable Timer 5–20 seconds: Fixed-duration pulse control keeps residents from wedging a strike open indefinitely. At a 12-second setting, the door strike releases automatically after a visitor buzzes in, preventing abuse and reducing mechanical wear on the solenoid.
• 24V DC Low-Voltage Operation: All signal and relay logic runs on 24V DC from a centralized PS-2420 supply. No high-voltage wiring inside the cabinet — lower installation risk and easier field termination, especially in older buildings where code enforcement is strict about low-voltage separation.

Deployment Considerations:

• The GT-OP2 is a frame only; you must add a module card (camera, door handset, etc.) to get a complete station. Don't assume it comes as a turnkey unit — plan for module procurement and stocking separately.
• The 3A normally-closed relay is adequate for a single 120V AC chime, but not for simultaneous multi-load switching. If you need to control a strike and two auxiliary circuits at once, run the N/O relay as primary and cascade an external 24V relay for secondary outputs.

Best fit: small multi-family buildings (up to 8 units) with a single GT base station and distributed door intercoms. The modular frame keeps wiring organized, the relay ratings are sufficient for one or two strikes per building, and the timer feature prevents abuse in shared-entry scenarios.