Operating Manual
21
6 Instrument description
Operating
mode
as per EN 60 730-1
TW: Type 2BL = automatic mode
with microswitch disconnection in operation,
which requires no auxiliary energy source.
STB, STW (STB): Type 2BK = automatic mode
with microswitch disconnection in operation,
with fail-safe facility.
Operating position
unrestricted (with open-air mounting on request)
Weight approx. 0.65 kg
Capillary and
probe materials
Minimum
bending radius
5mm
Switching point
accuracy
(in % of scale range;
in relation to the set point or limit value at +22 °C ambient temperature)
TW in upper third of scale
± 1.5%
at start of scale
± 1.5%
STB, STW (STB) in upper third of scale
at start of scale
Mean ambient
temperature
influence
(in % of scale range) in relation to the limit value
There is a displacement of the switching point if the ambient temperature at
the thermostat head and/or the capillary deviates from the +22 °C calibration
ambient temperature.
higher ambient temperature = lower switching point
lower ambient temperature = higher switching point
End of scale Capillary Probe
up to +200 °C copper Mat. Ref. 2.0090
tin-plated, 1.5 mm dia.
copper Mat. Ref. 2.0090
tin-plated, brazed
up to +300 °C copper Mat. Ref. 2.0090
tin-plated, 1.5 mm dia.
stainless steel
Mat. Ref. 1.4571, brazed
up to +500 °C stainless steel,
1.5 mm dia.
stainless steel
Mat. Ref. 1.4571, welded
+0
-5
%
+0
-10
%
for temperatures with end of scale:
below +200 °C +200 °C to +350 °C
TW STB/STW (STB) TW STB/STW (STB)
influence on thermostat head, % per °C
0.08 0.17 0.06 0.13
influence on capillary, % per °C per m length
0.047 0.054 0.09 0.11