Operating
Instructions GB
SF6 Gas Density Monitors
with magnetic snap-action contacts
(Models 233.52.100, with gas or
liquid filling as well as Model 212.22.100)
Examples:
3. Description, application
The built-in electric alarm contacts (magnetic
snap-action) are auxiliary current switches
which open and close the connected electrical
circuits at the set points via the contact arm,
which is driven by the main instrument
pointer.
4. Mechanical connection
According to the general technical regulations
for pressure gauges, respectively (i.e. EN 837-2).
When screw-fitting the gauges the force
required for this must not be applied through the
case or terminal box but just through the
spanner flats (with suitable tool) provided for
this purpose.
Model 233.52.100,
with external
temperature sensor
Model 233.52.100
Contents
1. Safety instructions
2. General information
3. Description, application
4. Mechanical connection
5. Wiring details
6. To set desired value indicator
7. Ingress protection IP
8. Admissible ambient temperatures
9. Maintenance and servicing / cleaning
10. Power ratings
11. Overcurrent protection devices
12. Repairs / Complaints
1. Safety instructions
The appropriate national safety
regulations (i.e. VDE 0100) must be
observed when installing, putting into
operation and running these
while under voltage.
Serious injuries and/or damage can occur
should the appropriate regulations not be
observed.
Only appropriately qualified persons should
work on these instruments.
2. General information
Gas density monitors are modified pressure
measuring instruments with electrical
accessories. Gas density monitors combine
both measuring and switching functions in one
single instrument. Temperature influences that
have an effect on the confined SF6 gas are compensated by means of a compensation system.
Each density monitor is specially adapted to the
specific application conditions of the switchgear
it is intended for (pure SF6 gas, gas compounds,
calibration pressure, switching points ...).
During transportation or storage gas density
monitors might warm up or cool down.
Temperatures that are different from the
reference temperature (20 °C) lead to pointer
deflections. This is absolutely normal, because
the compensation system is working.
In order to ensure that the instruments have
sufficiently adjusted to the ambient temperature,
they have to be exposed to a temperature of 20
±2 °C for at least 2 hours. Subsequently in an
unpressurised condition the pointer will be
within the tolerance bar.
instruments. Do not work on gauge
Installation with
open-end wrench
5. Wiring details
The electrical connections should be made by
qualified electricians. Connection details and
switch functions are given on the instrument
type plate.
Connection terminals and ground terminal are
appropriately marked. The main connection line
to be provided must be dimensioned for
maximum instrument power consumption and
comply with IEC 227 or IEC 245.
Power ratings and overcurrent protection
devices see overleaf!
6. To set desired value indicator
As a standard the alarm contacts of SF6 gas
density monitors are non-adjustable, i.e. they
cannot be re-adjusted later on. Therefore the
risk of unintentionally mis-adjusting the alarm
contacts is eliminated.
Desired value
indicators
(red set pointer)
If on express request by the customer the
contacts have to be adjustable, re-adjustments
can be carried out as follows:
The desired value can be set via the adjustment
lock in the window by means of the readjustment key provided (at the terminal box
of standard instruments).
7. Ingress protection IP
The type of enclosure to EN 60 529 for
protection against external influences depends
on the basic instrument and is found in the
respective data sheet.
8. Admissible ambient temperatures
The permissible ambient temperatures for alarm
contacts is -20 to +70 °C. Where this span
exceeds the permissible temperature limits for
the instrument to which the contacts are fitted,
the limits for the instrument apply (see data sheet).
9. Maintenance and servicing / cleaning
The instruments require no maintenance or
servicing. The instruments should be cleaned
with a damp cloth moistened with soap solution.
For cleaning inside the instrument the mains
power supply should be disconnected by
means of the plug box or plug connection.
It must be ensured that all the parts are dry
before the power is switched on again.
10. Power ratings
Table 1: Maximum contact rating
Maximum contact rating Magnetic snap-action contact model 821
with non-inductive
Gas filled gauges Liquid filled gauges
(ohmic) load
Maximum voltage (MSR) U
eff
Current ratings:
Make rating 1.0 A 1.0 A
Break rating 1.0 A 1.0 A
Continous load 0.6 A 0.6 A
Maximum load 30 W 50 VA 20 W 20 VA
Note: None of the limit values for voltage,
current and capacity are to be exceeded!
We recommend the following load values to
ensure safe, continuous operation:
Table 2: Recommended contact ratings with
different nominal voltages and instrument
versions
250 V 250 V
Voltage Magnetic snap-action contact model 821
(DIN IEC 38) Gas filled gauges Liquid filled gauges
DC / AC
ohmic load inductive ohmic load inductive
load load
DC AC cos ϕ >0.7 DC AC cos ϕ >0.7
VmAmAmAmAmAmA
230 100 120 65 65 90 40
110 200 240 130 130 180 85
48 300 450 200 190 330 130
24 400 600 250 250 450 150
The switching current must not be less than 20 mA
with low voltages for switching reliability reasons.
For higher loads, and instruments with liquid-filled
cases, we recommend the use of a separate relay,
WIKA Models 905.1X.
11. Overcurrent protection devices
No overcurrent protection devices are installed
in the instruments.
Should overcurrent protection devices be
required we recommend the following values in
12. Repairs / Complaints
Repairs are to be carried out by the
manufacturer only. The instruments must not be
opened, as this would result in indication and
switching point errors.
accordance with EN 60 947-5-1.
In the case of complaints the manufacturing and
Voltage 24 V: 2 A
Voltage 250 V: 1 A
product identification numbers have to be
stated. The manufacturing number is indicated
on the dial, the product identification number on
Data refers to miniature fuses M and
a maximum short circuit current 100 A.
the type plate. When measuring, the
atmospheric pressure, the temperature during
measurement and the data of the reference
standard (model, class) always have to be
indicated.
The density monitors have to be exposed to a
specific temperature long enough (at least 2
hours) to ensure temperature equalisation.
WIKA Alexander Wiegand GmbH & Co. KG
Alexander-Wiegand-Straße 30
63911 Klingenberg • Germany
Phone (+49) 93 72/132-0
Fax (+49) 93 72/132-406
E-Mail SF6@wika.de
info@wika.de
www.wika.de
Technical alteration rights reserved.
9078061 01/2003 GB/D/F