The **PRU-22-R/Q** is an Industrial Multi-Voltage Timer Relay, commonly used in automation, control panels, and HVAC systems. It is designed to control electrical loads by introducing time delays into a circuit. Below is a breakdown of its electronic components, technical specifications, and functions. --- ### 1. Key Electronic Components & Construction | Component | Description | | :--- | :--- | | **Microcontroller / ASIC** | The "brain" that handles the timing logic and ensures precision across temperature fluctuations. | | **Electromechanical Relay** | The output stage (SPDT/DPDT) that physically opens or closes the circuit. | | **Potentiometers** | Rotary dials on the faceplate used to manually set the time duration and scale. | | **Multi-Voltage Power Circuit** | A switching regulator or transformerless power supply allowing it to accept AC or DC (12V-240V). | | **LED Indicators** | Visual diagnostics for Power (Ready) and Relay Status (Active). | --- ### 2. Technical Specifications The electronic performance of the PRU-22-R/Q is defined by the following parameters: * **Supply Voltage:** Universal range, typically **12V - 240V AC/DC**. * **Output Contacts:** Single Pole Double Throw (**SPDT**) or Double Pole Double Throw (**DPDT**). * **Current Rating:** Usually rated for **8A to 10A** at 250VAC. * **Timing Range:** Adjustable from **0.1 seconds to 100 hours** (depending on the specific sub-model). * **Mounting:** Standard **35mm DIN rail** mount. --- ### 3. Electronic Functions (Operating Modes) The "R/Q" designation often refers to specific timing logic pre-programmed into the electronics: 1. **On-Delay:** The relay waits for a set time after receiving power before energizing the output. 2. **Off-Delay:** The relay energizes immediately but remains on for a set time after the trigger signal is removed. 3. **Flicker/Pulse:** The relay cycles ON and OFF at set intervals. 4. **Signal OFF-Delay:** Triggered by an external control contact. --- ### 4. Wiring and Terminal Layout The electronic terminals are standardized to ensure safe integration: * **A1 / A2:** Power supply inputs (Non-polarized for DC in most universal models). * **15 / 16 / 18:** Common, Normally Closed (NC), and Normally Open (NO) contacts for the first pole. * **25 / 26 / 28:** Second pole contacts (if DPDT). * **S:** Control/Signal input (for triggered modes). --- ### 5. Protection Features * **IP20 Protection:** Touch-proof terminals to prevent accidental shock. * **Self-Extinguishing Plastic:** The housing is made of flame-retardant materials. * **Noise Immunity:** Internal filtering to prevent false triggering from electromagnetic interference (EMI).