User Manual

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Siemens Temperature monitor / safety temperature limiter for flue gas ducts RAG-TW.1/-ST.1 CE1N1211en
Building Technologies 21.12.2010
Use
Typical applications:
•
Heat generation plants with several heat sources, for switching from solid fuel to oil or
gas boiler, and vice versa
•
To ensure safe flue gas ducts in plants operating at low flue gas temperatures
•
Suited for industrial and residential sectors
•
Unit is fitted to a protection pocket for immersion in the flue gas duct
Functions
Temperature monitor RAG-TW.1
When the flue gas reaches the adjustable limit temperature, the RAG-TW1 opens
contact 1-2 and closes 1-3. When the temperature of the flue gas falls by the value
of the switching differential (about 15 °C below the limit temperature), the RAG-
TW1 resets itself automatically (contact 1-2 closes and 1-3 opens).
Safety temperature limiter RAG-ST.1
When the flue gas reaches the adjusted limit temperature, the RAG-ST1 opens
contact 11-12 and closes 11-13 to remain tripped in this position. When the
temperature of the flue gas falls by the value of the switching differential (about
20 °C below the limit temperature), the RAG-ST1 must be manually reset after
removal of the threaded nipple. When resetting the RAG-ST.1, contact 11-12
closes and 11-13 opens.
Should expansion liquid escape, resulting from a leak in the sensing system (e.g.
in the capillary tube), the pressure in the diaphragm drops, causing the microswitch
to open contact 11–12.
Type summary
Mounting notes
Refer to the Mounting Instructions enclosed in the package.
When ordering, please give product no. according to ”Type summary” (standard
kit).
Mechanical design
• Housing made of PC (reinforced), designed for pocket mounting of RAG-ST.1
or RAG-TW.1 with capillary tube, protection pocket and spacer
• Cable entry gland M16 x 1.5 mm
• Cover made of PC, with viewing window and a removable threaded nipple for
resetting the RAG-ST1
• Properties of PC:
- Flame-resistant
- UV-protected, weather- and aging-resistant
- Resistant to higher temperatures
- Highly resistant to chemical, mechanical and biological influences
Product no. Stock no. Temperature range
Protection pocket
length
RAG-TW.1 S55700-P134 40…230 °C
150 mm
RAG-ST.1 S55700-P135 40…230 °C
150 mm
Ordering
Housing