Ross Controls LOW TEMPERATURE SERIES 21 User Manual

Page 3

Vacuum service valves are ideal for lifting, holding, vacuum
packaging and moving anything from large objects to tiny
particles. They also provide Vacuum service valves are ideal
for lifting, holding, vacuum packaging and moving anything from
large objects to tiny particles. They also provide an effective
means for leak testing. The vacuum source typically comes
from either a vacuum pump or a venturi. In vacuum service
applications, the pressure within the valve is reduced below
atmospheric pressure. Consequently, atmospheric pressure
actually pushes air into the valve, instead of the common belief
that air is “sucked” in by the vacuum.
In normal valves, filters exist to clean compressed air, which is
then pushed through the valve. In vacuum valves, there is no
filter, and the air comes from the atmosphere and enters through
the outlet, bringing with it atmospheric and nearby surface dust
and dirt. Vacuum valves, in order to function consistently, must
therefore be highly tolerant of the particles that freely flow into
the valves.
To construct a vacuum service valve system, typically a 3/2
normally closed valve is used. The vacuum is on the inlet, while
the exhaust remains open to atmosphere. Port 2 is the working
port. However, if there is a need for the vacuum service valve to

function as normally open, simply connect the vacuum source to
the exhaust and port 1 to atmosphere. Several variations of this
construction are effective, including using 2/2 valves.

“Full Vacuum” Valves

Though there are fewer applications for full vacuum valves
than regular vacuum valves, full vacuum valves are ideal for
applications where compressed air is unavailable. Full vacuum
valves use the difference in force between atmospheric pressure
and the vacuum within the valve to actuate the valve. The full
vacuum valve performs with atmospheric pressure in port 1 and
10 to 30 inches of Mercury vacuum in the valve body.

Remote Air or Solenoid-Piloted Vacuum Valves

Pilot vacuum valves provide a greater variety of applications,
operating with a combination of vacuum and atmospheric
pressure. The pilot must be supplied externally with a minimum
of 30 psig. Vacuum valves can be used as either 3/2 normally
closed or normally open valves, with vacuum supplied at either
port 1 or port 3. Normally closed and normally open 2/2 versions
are also available.

What are Vacuum Service Valves?

Series 21 Poppet Valves for Line Mounting

4/2 Valves – Double Direct Solenoid Controlled, Detented

Port Sizes Valve Model Avg.

Dimensions inches (mm)

Weight

In-Out Exh.

Number

lb (kg)

1/4 1/2

2176C2003 2.5

8.9 (226)

3.9 (97)

6.9 (176)

4.0 (1.8)

3/8 1/2

2176C3003 3.6

8.9 (226)

3.9 (97)

6.9 (176)

4.0 (1.8)

1/2 1/2

2176C4013 3.7 8.9 (226)

3.9 (97)

6.9 (176)

4.0 (1.8)

1/2 1

2176C4003 6.9

8.9 (226)

5.2 (132)

8.7 (221)

6.5 (3.0)

3/4 1

2176C5003 8.2

8.9 (226)

5.2 (132)

8.7 (221)

6.5 (3.0)

2176C6013 8.9

8.9 (226)

5.2 (132)

8.7 (221)

6.5 (3.0)

11/2

2176C6003

8.9 (226)

8.2 (208)

10.4 (265) 13.3 (6.0)

11/4 11/2

2176C7003

8.9 (226)

8.2 (208)

10.4 (265) 13.3 (6.0)

11/2 11/2

2176C8013

8.9 (226)

8.2 (208)

10.4 (265) 13.3 (6.0)

STANDARD SPECIFICATIONS: For valves listed above.
Solenoids: AC or DC power.
Standard Voltages: C

onsult ROSS.

Power Consumption: Each solenoid; 190 VA inrush, 40 VA
holding on 50 or 60 Hz; 20 watts on DC.
Indicator Lights: In each solenoid housing.
Ambient Temperature: 40° to 120°F (4° to 50°C).
Media Temperature: 40° to 175°F (4° to 80°C).
For temperatures below 40°F (4°C) air must be free of water
vapor to prevent formation of ice.

Flow Media: Filtered air; 5 micron recommended.
Inlet Pressure: 30 to 150 psig (2 to 10 bar).
Pilot Pressure: If external supply is used, pressure must
be equal to or greater than inlet pressure.
Threads: Model numbers above specify NPT pressure port
threads. For other threads, consult ROSS.

IMPORTANT NOTE

Please read carefully and thoroughly

all of the

CAUTIONS on the inside back cover.