For cold air, slow opening, slow closing, for 120 V AC
VR 25R01RQ31D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85279300
VR 40/32R01RQ31D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85250300
VR 40R01RQ33D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85247170
VR 50R01RQ33D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85248270
VR 65R01RQ33D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85249220
Bypass orifice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . surcharge
VR versions
Designation Order no.
Solenoid valve with socket and LED . . . . . . . . . . . . . . . . . . . . . . . . surcharge
Solenoid valve for 24 V DC
DN 6 to DN 50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . surcharge
DN 65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . surcharge
3 Valves and butterfly valves
2-66
 
Pressure switches for gas DG
Diaphragm pressure switches with micro switch (silicone-free) for monitoring gas pressures on industrial installations and heating systems, for gas, air and flue gas, also for
biogas, DG..H/N with manual reset if the pressure rises above or falls below a switching
point, for 24-250 V, with gold contacts also for 5-250 V, enclosure IP 54 (IP 65), EU certified pursuant to the Gas Appliances Directive and DIN EN ISO 13849. As special-design
pressure switches as defined by VdTüV Code of Practice “Druck 100/1” (Pressure
100/1), they are suitable for applications in firing installations for steam and hot-water
generators in accordance with TRD 604, Para. 3.6.4 and Class “S” pursuant to EN
1854. The units are certified up to and including PL e in accordance with DIN EN ISO
13849 and up to and including SIL 3 in accordance with DIN EN 61508. The suitability
for certain applications can only be evaluated by taking into account the relevant safetyrelated complete system with regard to the requirements of DIN EN 61508 or DIN EN
ISO 13849.
All pressure switches DG..G with gold contacts can be used with an isolating amplifier in
zone 1 and 2 hazardous areas.
The pressure compensation holes of series DG..U, B, H, N, I have a defined ignition
protection in terms of the safety measure for enclosed break devices for Group IIA gases
and vapours. They can therefore be operated on pipes with zone 2 explosive atmospheres.
Type Connection Adjustment El. connection Contact
DG..C pos. pressure (gas/air) fixed socket NO/changeover
DG..VC pos. pressure (gas/air) hand wheel socket NO/changeover
DG..B pos. pressure (gas/air) hand wheel terminals/socket change-over
DG..U pos. pressure (gas/air)
neg. pressure (air) hand wheel terminals/socket change-over
DG..H/N pos. pressure (gas/air)
neg. pressure (air) hand wheel terminals/socket change-over
DG..I neg. pressure (gas/air) hand wheel terminals/socket change-over
Pressure switches for oxygen and ammonia DG..S
Diaphragm pressure switches with micro switch for monitoring oxygen and ammonia
pressures (not suitable for natural gas, other media on request), for positive pressure,
diaphragm material: IIR, with CE marking, not EC type-tested, without Class “S”.
Type Connection Adjustment El. connection Contact
DG..S pos. pressure (O2/NH3) hand wheel terminals/socket change-over
Technical
Information DG
4 Pressure switches
4 Pressure
switches
2-67
Pressure switches for gas DG..C
Type code
DG Pressure switch for gas
15 Adjusting range 3-15 mbar
17 Adjusting range 2-17 mbar
30 Adjusting range 8-30 mbar
35 Adjusting range 5-35 mbar
40 Adjusting range 5-40 mbar
45 Adjusting range 10-45 mbar
60 Adjusting range 10-60 mbar
110 Adjusting range 33-110 mbar
150 Adjusting range 40-150 mbar
250 Adjusting range 70-250 mbar
300 Adjusting range 100-300 mbar