Type 59A8: Electric fire detection switches with thermal glass bulb for air duct


Fire detection in air ducts. This device operates electrical contacts for remote alarm and simultaneous control of electrical servo-controls such as electric cylinders, electric motors or solenoids, for opening or closing air conditioning dampers.


Main Features

Thermal sensitive part: Thermal bulb

Operation: The break of the bulb activates, by means of a plunger, an electric switch.

Mounting: Enclosure with removable mounting bracket made of stainless steel allowing the mounting perpendicular to an air duct with the diameter 12mm probe located in the air flow through the pipe wall. Mounting of this bracket on another face of the housing is possible

Electrical contact: Double snap action contact with two independent circuits, one normally open and the other normally closed. Total contacts spacing is larger than 3mm, providing full disconnection upon IEC standards.

Electrical rating: 16A (4A) 250VAC; 10A (1A) 400VAC; 4A (100mA) 24 and 48VDC. Compatible with electric door magnets in 24V and 48V, 500 N.

(Version with gold plated contacts for low level electronic circuits available on request).

Enclosure: 70 x 80 x 35mm in UV resistant black PA66, with captive lid screws in stainless steel.

– Flammability: UL94V0 and GWFI 960°C.

– Deformation temperature under load: 225°C. (ISO 75-2, 1.8 MPa).

– Ambient temperature class T150°C.

– Resistance to corrosion better than 1000 hours in salt spray fog at 5%.

– Ingress resistance: The highest class, IP69K (washable at high pressure hot water cleaner).

– Impact resistance: The highest class, IK10 (except stainless steel support for temperature-sensitive parts and glass bulbs).

Electrical connection: On screw terminal block, 7 terminals 2.5mm². Shipped with a 3-way shunt and a 2-way shunt, allowing different contact and connection arrangement solutions. Cable outlet by two M16 cable glands.


– Easy replacement of the temperature-sensitive part

– A test button (option) accessible from the outside allows to check instantly the operation of the switch without any disassembly or opening.

– The enclosure has holes for the installation of seals preventing unauthorized opening.

Visualization: Optional 230 V, 24V or 48V pilot light. This pilot light can be used to visualize the presence of voltage on the line, a critical parameter for “contact closes on fire” detection systems.

Other options: Customization and customer labelling. Output by a single cable gland.




2D&3D Drawing

Main references 

Operating temperature Reference without test button, without pilot light Reference without test button, with 230V pilot light* Reference with test button, without pilot light Reference with test button and 230V pilot light**
Without thermal bulb 59A80PS1630003C 59A81PS1630003C 59A8AP2S1630003C 59A8BP2S1630003C
57°C (135°F) orange color bulb 59A80PS1630573C 59A81PS1630573C 59A8AP2S1630073C 59A8BP2S1630573C
68°C (155°F) red color bulb 59A80PS1630683C 59A81PS1630683C 59A8AP2S16300683C 59A8BP2S1630683C
79°C (174°F) yellow color bulb 59A80PS1630793C 59A81PS1630793C 59A8AP2S1630793C 59A8BP2S1630793C
93°C (199°F) green color bulb 59A80PS1630933C 59A81PS1630933C 59A8AP2S1630033C 59A8BP2S1630963C
141°C (286°F) blue color bulb 59A80PS1631413C 59A81PS1631413C 59A8AP2S1631413C 59A8BP2S1631413C

* -For models without test button with 24V pilot light, replace 1P by 2P in the reference

-For models without test button with 48V pilot light, replace 3P by 1P in the reference

** -For models with test button with 24V pilot light, replace BP by CP in the reference

-For models with test button with 48V pilot light, replace BP by DP in the reference