Safety Instructions; Testing The Display - WIKA 811 Instrucciones

1. Safety instructions / 2. Testing the display

1. Safety instructions

The appropriate national safety regulations (i.e. VDE 0100 /
!
EN 837-) must be observed when installing, commissioning and
GB
operating these instruments.
Caution
Only appropriately qualified personnel should work on these instruments

Pressure gauges may only be removed once they are free from pressure

Any residual pressure medium contained in the pressure element may be

hazardous or toxic. This should be taken into account when handling and
storing pressure gauges which have been removed.
Serious injuries and/or damage can occur should the appropriate regulations

not be observed

2. Testing the display

Basic testing principles
The accuracy class is tested in accordance with EN 837

The display is always tested in accordance with the operational error limit

The test is carried out with rising and falling pressure. With gauges that have

a free zero point the lower limit and the upper limit of the scale range are
used as the measuring points.
The pressure gauge used as a measuring standard must be at least four

times as accurate as the device to be tested:
e.g.: Device under test = Class 1.6
The measured values indicated are recorded after gently knocking on the

case
For pressure gauges with electrical alarm contacts, the set point indicator(s)

should be set so that any load on the actual value pointer is eliminated as
far as possible. The test of the scale range when the alarm contacts are
change-over contacts is carried out with the contacts at 1 o'clock (both
contact arms load the actual value pointer).
4
⇒
Test variable ≤ Class 0.5
WIKA Testing Instructions for Pressure Gauges