Data sheet 60.1530 Page 1/6 Rod thermostat with micro switch STMA type series Particularities with micro switch Aluminum die cast case Protection class IP 54 high over-temperature security high response sensitivity Brief description Rod thermostats with micro switches operate according to the rod length expansion principle. During this process, the temperature dependent thermowell length change is transmitted via an internal rod, having a smaller expansion coefficient and being fitted in the thermowell, to a transmission unit equipped with a micro switch integrated in the switch head. The thermostats of the STMA type series are used, for example, in the heating and air conditioning technology. Rod thermostats are distinguished by their high over-temperature security independent of the control range (max. +345 C), high response sensitivity (time constant 8 s) and negligible low ambient temperature influence at the switch head. When the thermowell is damaged or bent, the thermostat changes over to the "Safe status (heater off). STMA-1 Switching function Temperature controller TR and temperature monitor TW If the temperature exceeds the set point value set on the temperature probe, the micro switch will be tripped via the transmission mechanics and the current circuit opened or closed. The micro switch is reset to its original status once the set point value set is gone below (by the hysteresis). Temperature limiter TB If the temperature exceeds the limit value set on the temperature probe, the current circuit is opened and the micro switch mechanically locked. The micro switch can be manually unlocked, once the dangerous temperature is gone below by approx. 10 % of the scale range. Temperature limiter TB with extra code 574 The additional N/O contact can be used as a signal contact. STMA types STMA type -1-2 -7 Switching function Temperature controller TR Temperature monitor TW Temperature limiter TB
Data sheet 60.1530 Page 2/6 Technical Data General information Control ranges, hysteresis and immersion tube length Control ranges C Hysteresis in K Immersion tube length S active immersion tube length -10...+100 +5...+160 0...+300 0...+75 +15...+120 +5...+160 0...+240 0...+80 0...+120 +20...+200 +50...+300-80...+100 0...+50 +20...+150 0...+200-15...+50 0...+40 0...+80 4 ± 1 100 mm 100 mm 3 ± 0.7 150 mm 150 mm 2.5 ± 0.4 200 mm 200 mm 1.9 ± 0.4 250 mm 250 mm 1.6 ± 0.4 300 mm 300 mm Electrical data STMA-1 STMA-7 STMA-7 / U Switching element Micro switch with changeover contact Micro switch with changeover contact Micro switch with N/C contact and restart lock Micro switch with N/C contact, restart lock and additional signal contact maximum contact rating 230 VAC +10%, 10 (2) A, cos ϕ = 1 (0.6) DC 230 V +10%, 0.25A Operating data Switching point accuracy ± 1.5% of the scale range, in the scale range centre, referring to the switch-off point in % admissible storage temperature -50...+50 C admissible ambient temperature -40...+80 C when in use Rated position as per DIN 16 257, rated position 0... rated position 90 (different rated positions upon request) Case Case Aluminum die cast, surface with impact resistant textured paint; lid: RAL 7032, bottom section: RAL 7015 Cable inlet Standard: clamping gland M 20 x 1.5 Surcharge: cable screw-connection M 20 x 1.5 as per EN 50262 CuZn Set point value setting STMA-1 / STMA-7 The switching point can be externally adjusted by means of the rotary knob Protection type EN 60 529-IP 54 Weight approx. 0.65 kg The switching point can be adjusted by means of a screwdriver once the case lid has been removed Process connection Version Material plain cylindrical probe Collar Ø 19 mm between case and probe CuZn (process connections U, g, b can be retrofitted) Screw-in sleeve Protection sleeve as a screw-in sleeve, screw-in spigot shape A as per DIN 3852/2 with locking screw, immersion tube Ø 12 mm up to 150 C CuZn, nickel plated / from 150 C CrNi Extra code 715 loose screw-connection M 18 x 1 with counter nut CuZn nickel plated Extra code 764 Mounting flange Sheet steel, galvanized fixed screw-connection with hexagon, width across flats 27, thread G1/2 CuZn nickel plated Probe Diameter 9 mm CuZn nickel plated Fitting length S 100, 150, 200, 250 and 300 mm
Data sheet 60.1530 Page 3/6 Wiring diagrams STMA-1 / STMA-7 STMA-7 / U Dimensions STMA-1 Process connection, extra code 764, STMA-1 Process connection, extra code 764,
Data sheet 60.1530 Page 4/6 Dimensions Process connection, fixed screw-connection, Process connection, extra code 715, Process connection, screw-in sleeve, Process connection, fixed screw-connection, Process connection, extra code 715, Process connection, screw-in sleeve,
Data sheet 60.1530 Page 5/6 Dimensions STMA-7 Process connection, smooth cylindrical probe, STMA-7 Process connection, smooth cylindrical probe,
Data sheet 60.1530 Page 6/6 Order details ( 1 ) Basic type 601530 Rod thermostat, type series STMA ( 2 ) Basic type extensions 01 STMA-1 Temperature controller TC with change-over contact 02 Temperature monitor TM with change-over contact 07 STMA-7 temperature limiter TB with N/C contact ( 3 ) Control / limit value range Range in C Immersion tube length in mm 020 0...+40 300 021 0...+50 250 015-15...+50 250 023 0...+75 150 024 0...+80 200 or 300 010-80...+100 200 017-10...+100 100 026 0...+120 200 037 +15...+120 150 043 +20...+150 250 035 +5...+160 100 or 150 028 0...+200 250 044 +20...+200 200 029 0...+240 150 030 0...+300 100 064 +50...+300 200 ( 4 ) Process connection 10 plain cylindrical probe 20 Screw-in sleeve 54 fixed screw-connection with hexagon ( 5 ) Thread of process connection 00 without thread 13 External thread G 1/2 ( 6 ) Material of process connection 46 CuZn (brass only with process connection 10, 20, 54 20 CrNi (stainless steel) only with process connection 20 ( 7 ) Fitting length "S (immersion tube length) Note: The control range depends on the immersion tube length. 100 100 mm 150 150 mm 200 200 mm 250 250 mm 300 300 mm ( 8 ) Extra codes 574 Change-over contact 715 loose screw-connection M 18 x 1 with counter nut 764 Fastening element ( 1 ) ( 2 ) ( 3 ) ( 4 ) ( 5 ) ( 6 ) ( 7 ) ( 8 ) Order code 601530 / - - - - - /,... Order example 6015301 / 02-26 - 20-13 - 46-200 / 000 a,... a State extra codes one after another, separated by commas.