since 1956 - celebrating our 63rd year!
Thermal Management for Enclosures
Call Today! (800) 321-KOOL
US Flag Made in the USA
Wednesday, June 20, 2018
home quote sitemap
Refresh browser to display menu

Mechanical Hygrostat,
Change-Over Contact

The KSMH is designed to control the relative air humidity inside of enclosures. When connected to an enclosure heater, (de-humidifier), it will turn the heater on at the set humidity level in order to raise the dew point. This helps prevent damage and malfunction of electronic components caused by condensation and corrosion.* The KSMH can also be used to control cooling fans, warning lights or other devices.


Mechanical Hygrostat
ce-crus logo
  RoHS logo
  • Contact Kooltronic for pricing
  • Adjustable relative humidity range
  • High switching capacity
  • DIN rail mountable


Model Number:
Adjustment range:
35-95% (±3.0%) relative humidity
Switching difference (hysteresis):
Approx. 4% RH @ 50% relative humidity
Permissible air velocity: 50 ft/sec (15m/s)
Maximum switching voltage: 250 VAC (NOTE: 250 V should only be switched in a non-condensing environment!)
Contact type: Change-over contact
Contact resistance: <10mΩ
Service life 50,000 cycles
Minimum switching capacity:
100mA @ AC/DC 20 V
Maximum switching capacity: 5A @ AC 230 V (resistive load)
  0.2A @ AC 230 V
  (inductive load at cos φ = 0.8)
  DC 20W
EMI/EMC compliance: EN 55014-1-2, EN 61000-3-2, EN 61000-3-3
Connection: 3-pole terminal, 3 x AWG 14 max. (2.5 mm²)
Mounting: Clip for 35mm DIN rail (EN 50022)
Housing: Plastic, UL94V-0
Weight: 2 oz (60g)
Operating temperature: 32 to 140°F (0 to 60°C)
Storage temperature: -4°F to 176°F (-20 to 80°C)
Protection type: IP20
Application examples: Electrical & Electronic enclosures
  Telecommunication systems
  Display panels
  Ticket dispensers
  Automatic teller machines (ATM's)
  Access & Parking control systems
DIMENSIONS (click and drag to pan)
Dimensions, inches [mm], are for reference only and subject to change.
Specifications are subject to change without notice. Suitability of this product for its intended use and any associated risks must be determined by the end customer/buyer in its final application.
* The critical relative humidity for most components is 65%. Above 65% RH, condensation can cause malfunction of electronic equipment. Long term, this can lead to corrosion and permanent damage of electronic components and systems.
Series 21 Data Sheet
View Data Sheet
  Products - Services - News - Design Guide - Downloads - About Us - Manufacturing - Support - Contact Us We accept all major credit cards We accept Company Purchase Orders
  © 1996-2018 Kooltronic, Inc. - All rights reserved. - Terms of Use