Capillary Thermostat for Heat Trace Systems | Eltherm Ex-Capillary EL-CT ATEX

Eltherm Heat Trace Capillary Thermostat

The Eltherm Ex-Capillary Thermostat EL-CT, is designed for use with Heat Trace Systems in Hazardous Areas Zone 1 and Zone 2 for gas, and Zone 21 and Zone 22 for dust, acting as a surface thermostat on pipes and vessels. Offering safe, reliable and consistent heating without the need for an external power supply, the Eltherm Capillary Thermostat operates by directly switching the heating circuit on or off based on set temperature thresholds. Eltherm Ex Capillary Thermostat EL-CT Technical Drawings

ATEX & IECEx certified, the Eltherm Capillary Thermostat is made of stainless steel and the sturdy Exd housing is made of aluminium with brass cable glands.

Wall mounting
Sturdy Exd housing
Can be used for a wide range of applications
Seawater-resistance

Thorne & Derrick are approved stockists and suppliers of the complete Eltherm range, including a variation of Heat Trace Thermostats, Heat Trace Limiters & Hand-Held Controller Pads, all designed to increase safety and efficiency with your Trace Heating Systems. Contact our team of Heat Trace specialists today – we’ll help you get it right first time.

Eltherm Ex-Capillary EL-CT ATEX Technical Specifications

The following table provides a further insight on the Eltherm Capillary Thermostat, as well as further dimensional technical drawings provided below:

Eltherm Ex-Capillary Thermostat EL-CT Technical Specifications
Operating voltage	230 V AC ±10%, 50 Hz
Switching contact	1pole N/C contact
Switching capacity	16 A at 230 V [CT] / 10 A at 400 V [CT(2)]
Switching difference	230 V +/– 10 % [CT] / 400 V [CT(2)]
Hysteresis	2.5 % of end-of-scale value
Ambient temperature	-32 to +50 °C [CT], -50 °C to + 50 °C [CT(2)]
Housing material	Aluminium
Protection	IP 66
Dimensions	120 x 120 x 110 mm (WxHxD)
Weight	approx. 1.8 kg
Capillary material	Stainless steel 1.4571
Length of capillary tube	2 m
Bending radius of capillary tube	min. 5 mm

Eltherm Ex-Capillary Thermostat Dimensions

Eltherm Ex-Capillary Thermostat Dimensions

Ex-Capillary EL-CT Selection Guide

The following table provides a further insight on the complete Ex-Capillary EL-CT range, with product variations offering a wide range of temperature capabilities, aiding selection of the most suitable thermostat for industrial heat tracing operations:

Eltherm Ex-Capillary Thermostat EL-CT Selection Guide
Type	Setting range	Max. sensor temperature	Item no.
Eltherm EL-CT 30	-50°C up to +30°C	50°C	0X63030
Eltherm EL-CT 50	0°C up to +50°C	105°C	0X63050
Eltherm EL-CT 200	0°C up to +200°C	230°C	0X63200
Eltherm EL-CT 500	+20°C up to +500°C	575°C	0X63500
Eltherm EL-CT(2) 30	-10°C up to +30°C	60°C	0X63032
Eltherm EL-CT(2) 65	+5°C up to +65°C	100°C	0X63065
Eltherm EL-CT(2) 180	0°C up to +180°C	220°C	0X63180
Eltherm EL-CT(2) 320	+50°C up to +320°C	330°C	0X63320

Capillary Thermostat Applications

The Eltherm EL-CT Capillary Thermostat is a mechanical temperature controller that ensures safe, consistent heating in hazardous areas without the need for an external power supply. Used within trace heating systems, the EL-CT‘s robust, intrinsically safe design makes it ideal for applications where reliable thermal control is needed without complex electronics or programmable systems.

Petrochemical Plants
Maintains safe pipeline temperatures using mechanical control in explosive environments.
Gas Storage & Distribution
Prevents underheating or overheating of critical valves and flanges without requiring electrical monitoring.
Bulk Chemical Storage
Keeps chemicals within safe storage temperatures using a simple, fail-safe thermal switch.
Food Industry Process Lines
Ensures stable product temperatures (e.g., oils, fats) with durable mechanical control, even in washdown areas.
Water and Waste Systems in ATEX Zones
Prevents pipe freezing or overheating in exposed hazardous-area installations without the need for electronic controllers.
Remote or Off-Grid Installations
Ideal for isolated sites where reliable, passive thermal control is required and power sources are limited.
Adhesives & Coating Lines
Maintains material viscosity during transfer by switching heating circuits based on direct temperature sensing.

Eltherm | Heat Trace Solutions

German-Engineered Trace Heating Systems

As well as the Capillary Thermostat, Eltherm manufacture an extensive range of, silicone heating mats, trace heating cables, drum heaters, heating jackets, heating mats, heating mantles, heated hoses, trace heating tool boxes for hazardous areas (ATEX & IECEx certified). Thorne & Derrick’s team of specialists with 40+ years industry experience, are available to provide Custom Eltherm Trace Heating Systems, including complete specification and design, tailored to meet an extensive range of industrial and commercial needs.