WIKA Testing Instructions for Pressure Gauges
7
061744 09/
009 GB/D/F/E
GB
Meaning of the codes
Index 1: Contact makes when the instrument pointer approaches
the set point in a clockwise direction
⇒
NO contact
Index : Contact breaks when the instrument pointer approaches
the set point in a clockwise direction
⇒
NC contact
Index 3: Contact breaks one circuit and makes a second circuit when the
instrument pointer approaches the set point in clockwise
direction
⇒
SPDT contact. (not with Model 831)
Example of the contact model, contact type and function index
Model 81. 1 means:
81. = Magnetic snap-action contact
1 = Triple inductive contact (because of 3 digits)
= 1
st
contact breaks when pointer reaches set point (NC)
1 =
nd
contact makes when pointer reaches set point (NO)
= 3
rd
contact breaks when pointer reaches set point (NC)
Contact accuracy
The accuracy of the contacts is tested in accordance with EN 837 and DIN
16 085. The contacts are generally tested in ranges of 5 %, 50 % and 75 %
of the full scale value, provided that no other values or switching points are
specified.
Error limits
The deviation of the switching point from the set limit value must not exceed
the 1.5-fold value of the error limit of the pressure gauge.
The switching hysteresis may be:
With sliding contacts: max. 1 %
With magnetic snap-action contacts: between % and 5 %
With inductive contacts: max. 1 %
of the measuring span.
3. Testing of switch contacts
