The Saia PCD1.G1100-C15 is a freely programmable E-Line module purpose-built for light group switching and blind/shade control in building automation. Occupying just 35 mm (2 HP) of DIN rail, it functions as either a standalone miniature controller or an S-Bus networked slave under a Saia PCD master. Two 8 A changeover relays switch 230 VAC lighting or blind motor loads directly without external contactors, while two 0-10 V analogue outputs handle dimming actuators, valve positioning, or shade angle control.

What loads can the relay outputs switch directly?

Each of the two changeover relays is rated for 250 VAC / 30 VDC at 8 A (AC1/DC1) with a 15 A inrush capability — sufficient for direct switching of fluorescent banks, incandescent groups, and single-phase blind motors up to approximately 1,800 W at 230 VAC. Built-in load current measurement, active above 200 mA with 100 mA resolution, provides blind position feedback by detecting motor stall current, eliminating the need for external limit switches. No internal contact protection is fitted; external snubbers or varistors are recommended for inductive loads.

How does the module integrate into a building control system?

Galvanically isolated RS-485 with S-Bus protocol (500 VDC isolation) connects the module to the wider PCD system at baud rates from 9,600 to 115,200 bps with auto-bauding. Two rotary address switches set the S-Bus station address (0-253). The module can also run fully standalone: PG5 control programs execute from 64 kB of onboard Flash memory with 2,000 registers, 2,000 flags, and 200 timers/counters available to the application. An onboard real-time clock synchronises cyclically with the PCD master when networked.

How is the module programmed and commissioned?

Programming is via the Saia PG5 engineering tool using FBox libraries for lighting and blind control or native Instruction List (IL). The programme loads through the Micro USB service port or over NFC for fast commissioning of unpowered modules. Parameter backup to 2 kB of onboard EEPROM retains configuration through power cycles. Front-panel LED status indicators show run, communication, and I/O state at a glance.

What sensors and field devices connect to the inputs?

Four digital inputs accept 24 VAC or VDC in source or sink configuration (positive switching), with switching thresholds at 5 V (low) and 15 V (high). Input delay is configurable from 2 to 50 ms in DC mode or 20 ms fixed in AC mode, making them suitable for both conventional push-button sensors and active occupancy or lux sensors. The two 0-10 V analogue outputs feature 12-bit resolution (2.44 mV per step) with +/-0.3% accuracy at 25 C, short-circuit protection, and a hardware filter time constant of 2.5 ms for clean dimming or valve actuator control signals.