STR100
10460-0703-00
Page
3 / 8
www.ziehl.de
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Application and short description
The Safety Temperature Limiter type STR 100 is an electronic thermostat monitoring the temperature of heating
equipment and machinery. When the permitted temperature-limit is exceeded or in case of a malfunction, the
STR 100 switches off without delay. An active reset must be made for a restart. The temperature limit is
adjustable with a scaled potentiometer.
An unintended or unauthorized adjusting of the limit is prevented through a lead-sealed transparent cover.
With supply voltage switched on, the STR 100 operates in a changeable lockout mode and the relay must be
started by a reset (manually with built-in reset button or external reset) to make contact (no) close. Applicable
for plants with supervised operation. The mode of operation corresponds to type 2BJK according EN
60730/VDE 0631.
The temperature is measured with a Pt 100 resistance temperature detector (RTD) according to EN 60751 /
IEC 751. The process qualification in combination with the sensor must be proved. To fulfil affords for higher
safety functionality the function has to be routine-tested periodically. The thermostat series STR 100 meets
safety category 3 (Safety of machines EN 954-1, TÜV Rheinland documents T 24/00 + T103 2007 Z1 + T103
2007 E2). If safety approval is recommended only use listed RTD.
Temperature Limiter:
A temperature-limiter is an equipment that switches of permanently (locked) after the limit has been exceeded.
A reset (manually or with a tool) is possible after the temperature has fallen below switch-back point (limit minus
hysteresis).
Safety Temperature Limiter:
A safety temperature limiter is a limiter that fulfils in addition the requirements of extended safety according to
DIN 3440.
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Connecting diagram
RE SET 2
A2
A1
1
2
3
4
8
9
10
11
12
5
6
7
Pt 100
RESET 1
>
= 1
+
-
+
-
°C
&
K2
K1
U
s
+
R
E
AD
Y
/
ON
AL
AR
M
L1
N
11
14
12
22
21
Y2
Y1
T2
T1
-
DC 24V
