Power Supply 12V/1.25A (DIN)
User Manual

Power Supply 12V/1.25A (DIN)

SKU: PP-PWR-125A-DIN

Table of Contents

1. What you need

Wired. Mains AC input, DIN-rail mounted. Provides 12 V DC for PIERRE devices such as the Controller; size the supply to the total current of everything connected.

2. Product Description

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  1. V+, V-
  2. Upper connectors (green, black) - OUTPUT
  3. Voltage adjustment potentiometer
  4. DIN rail mounting
  5. Lower connectors (brown, blue) - INPUT
  6. N, L

3. Dimensions

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  • H: 90 mm
  • D: 58 mm
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  • W: 18 mm

4. Product specifications

Technical Specifications

Environmental

Operating Temperature -4°F ～ +158°F
Operating Temperature (°C) -20°C ～ +70°C
Operating Humidity 20%-90% RH, Non Condensing % RH
Storage Temperature -40°C - +80°C
IP Rating IP20

Features

LED Indicators Yes

Safety

Safety Features Overload protection, Over voltage protection, Short circuit protection

Electrical

Input Power 100-240V AC
Output Power 12V DC 1.25A 15W
Efficiency 85 %
Power Factor 0.98
Current 1.25 A

Physical

Product Color White
Mounting Type DIN Rail
Wiring Requirements N - Neutral, L - Live

5. Wiring

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  • Connect the AC input terminals to mains power: L (Live) and N (Neutral).
  • The output terminals V+ and V− supply 12 V DC. Connect V+ to the 12 V input of the device and V− to its GND.
  • Use the correct conductor cross-section and double-check polarity to avoid damaging connected devices.
  • Example wiring: From Power supply to Controller
Run Wires Cross-section Cable type Conductors
Example: From power supply to Controller 2 0.75 mm² NYM-J +12 V, GND

6. Functional Diagram

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Functional Diagram – System Overview

The diagram shows the internal stages of a switching mode power supply (SMPS) from AC input to regulated DC output.

Block descriptions:

  • I/P (Input): AC mains voltage is supplied to the power supply.
  • EMI Filter: attenuates conducted and radiated electromagnetic interference and protects downstream components.
  • Rectifiers & Filter (primary side): converts AC to DC and smooths the rectified voltage with capacitive filtering.
  • Power Switching Stage: a high-frequency switching converter (typically a MOSFET) chops the DC voltage to drive the transformer; switching is controlled by PWM (pulse width modulation).
  • Transformer: provides galvanic isolation between input and output and steps the voltage up or down.
  • Rectifiers & Filter (secondary side): converts the high-frequency AC from the transformer back to DC and filters ripple and noise. Delivers the output rails +V and –V.
  • Detection Circuit: monitors the output voltage and generates the feedback for regulation.
  • Control Circuit: processes the feedback and adjusts the switching duty cycle for a stable DC output.
  • O.L.P. (Over Load Protection): detects overload or short circuit on the output and limits the current or shuts the converter down.
  • O.V.P. (Over Voltage Protection): disables the power supply if the output voltage exceeds the set limit.

7. Derating Curve

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  1. Load (%)
  2. Ambient Temperature (°C)

8. Output Derating vs Input Voltage

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  1. Load (%)
  2. Input voltage (V AC), 60 Hz

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Last updated: October 06, 2026