Humidity and Temperature Sensor DHT22 Module

Specifications

• Operating Voltage: 3.3V to 6V DC.
• Sensing Range (Humidity): 0% to 100% RH (±2-5% accuracy).
• Sensing Range (Temperature): -40°C to 80°C (±0.5°C accuracy).
• Resolution: 0.1 (both temperature and humidity).
• Sensing Period (Sampling Rate): 2 seconds (0.5 Hz).
• Output Format: Digital signal via single-bus interface.
• Standby Current: <50µA.

Virtual Technician & Wiring ⚠️ WARNING: Wiring the power pins backward will permanently damage the sensor. Double-check your VCC and GND connections before powering on.

Wiring Guide (Standard 3-Pin Module):

• VCC: Connect to 3.3V or 5V on your Arduino/ESP32.
• DATA: Connect to any Digital I/O pin (e.g., Pin 2).
• GND: Connect to System Ground (GND).

Frequently Asked Questions 
Q: How is this different from the DHT11?
A: The DHT22 features a wider temperature range (-40 to 80°C vs 0 to 50°C) and much higher humidity accuracy (±2% vs ±5%). It is better suited for outdoor or precision use.

Q: Does this module require an external pull-up resistor?
A: No. This module version has a built-in 4.7k - 10k pull-up resistor on the data line, allowing for direct connection to your microcontroller.

Q: Can I read data faster than once every 2 seconds?
A: No. The sensor requires a minimum of 2 seconds between readings to provide accurate data. Querying it faster may result in stale or incorrect values.

Q: Is the sensor waterproof?
A: No. While it can handle high humidity, the sensor is not designed for direct contact with water or liquid immersion.

Applications

• HVAC Systems: Precise monitoring for smart air conditioning and dehumidifiers.
• Agriculture & Greenhouses: Ideal for automation systems where humidity control is critical for plant health.
• Medical Units: Used in isolation wards to maintain strict environmental parameters.
• Consumer Products: Integration into smart home weather stations and food storage monitors.

Cold Chain & Food Logistics

• Refrigerated Transport: Monitoring the temperature of perishable goods, vaccines, or dairy products during transit to ensure they stay within safety limits.
• Cold Storage Warehouses: Large-scale humidity monitoring to prevent frost buildup or spoilage in industrial freezers.

Technology & Infrastructure

• Server Room Monitoring: Integrating into a rack-mounted system to trigger emergency cooling or alerts if the environment gets too hot or humid (preventing short circuits).
• Battery Storage Enclosures: Monitoring Lithium-ion battery banks in solar setups to ensure they operate within safe thermal limits.

 Package Includes:

• 1 X Humidity and Temperature Sensor DHT22 Module
• 1 x 3-pin Connection Cable