
Selec HC205 4 Digit Dual Display Humidity Controller
Selec HC205 Digital Humidity Controller – 72×72 mm, 4-Digit Display, Dual 10A Relays, RH Sensor Included
Industrial-grade humidity controller with 0–100% RH measurement, dual 10A relay outputs (control + alarm), 4-digit LED dual display, onboard RH sensor input, 90–270V AC/DC supply, and ON/OFF control for HVAC & environmental systems.
Selec HC205 is a rugged and compact humidity controller designed for industrial and HVAC applications. It features a dual 4-digit LED display, ON/OFF humidity control, dual 10A relay outputs, a built-in RH sensor interface, adjustable display offset, and wide 90–270V AC/DC operation. Its panel-mount 72×72 mm design makes it suitable for control panels, environmental chambers, dryers, and storage areas.
KEY FEATURES
4+4-digit dual LED display (white 16.7 mm & green 9 mm digits)
Built-in RH sensor input (HS-A-100)
Sensor included with the unit
0–100% RH control range
ON/OFF control action
Dual 10A relay outputs (control + alarm)
90–270V AC/DC supply
0.1 / 1 %RH resolution
Offset adjustment up to 99.9
Sampling time: 250 ms
IP-rated front panel with capacitive keys
Compatible with IDM (Independent Downloader Module)
TECHNICAL SPECIFICATIONS
1. Display Specifications
| Parameter | Value |
|---|---|
| Display Type | 4+4 digit LED dual display |
| Digit Height | White: 16.7 mm, Green: 9 mm |
| Indicators | OUT1 (RH control), AL1 (Alarm) |
| Units | %RH |
2. Input Specifications
| Parameter | Value |
|---|---|
| Sensor Type | RH (HS-A-100) |
| Input Range | 0–100% RH |
| Input Signal Range | 5V DC |
| Sampling Time | 250 ms |
| Input Filter (FTC) | 0.2 to 10.0 sec |
| Resolution | 0.1 / 1 %RH |
3. Output Specifications
| Output | Type | Rating |
|---|---|---|
| RH Control Output | Relay SPDT | 10A at 250VAC / 30VDC |
| RH Alarm Output | Relay SPDT | 10A at 250VAC / 30VDC |
4. Functional Specifications
| Function | Range |
|---|---|
| Control Action | ON/OFF |
| Display Offset | 0.1 to 99.9 |
| Humidity Control Range | 0–100% |
| IDM Support | Yes—upload/download programs |
5. Power Supply
| Parameter | Value |
|---|---|
| Supply Voltage | 90–270V AC/DC |
| Power Consumption | 5 VA max |
6. Environmental
| Parameter | Value |
|---|---|
| Operating Temperature | 0°C to 50°C |
| Storage Temperature | −20°C to 75°C |
| Humidity | 95% RH non-condensing |
7. Mechanical Specifications
| Parameter | Value |
|---|---|
| Mounting | Panel |
| Main Unit Weight | 200 g |
| Sensor Weight | 33 g |
| Cable Length | 1 meter (extendable to 3 m; +1% error per meter) |
| Dimensions | 76 × 76 × 83.7 mm |
8. Terminal Connections
Terminals include:
L, N (Supply)
NO1, COM1, NC1 (Control output relay)
NO2, COM2, NC2 (Alarm output relay)
+5V, GND, Signal (RH sensor wires: Red, Black, Green)
9. Humidity Sensor Performance
Typical tolerance: ±2 %RH
Maximum tolerance: ±6% RH
Ratiometric analog output vs RH relationship illustrated
APPLICATIONS
HVAC humidifiers & dehumidifiers
Environmental test chambers
Storage room humidity management
Industrial drying and curing processes
Mushroom & food processing environments
Textile humidity stabilization
Cleanrooms & laboratories
WHAT’S IN THE BOX
Selec HC205 humidity controller
RH sensor (HS-A-100) with 1-meter cable
Panel clamp & mounting kit
User manual
FAQS
Q1. What is the power supply requirement?
90–270V AC/DC.
Q2. Are both relays 10A?
Yes—control and alarm relays both support 10A at 250VAC/30VDC.
Q3. How long is the RH sensor cable?
1 meter (extendable to 3 m, then +1% error per meter).
Q4. Does the unit include an RH sensor?
Yes—the sensor is enclosed with the unit.
Q5. What is the display type?
4+4-digit dual LED display with white & green digits.
Q6. Can the controller be used for both humidification and dehumidification?
Yes—via ON/OFF control logic.