Schneider Electric VA-7000 Series, VA-9000 Series, VF-7000 Series, VF-9000 Series, VS-7000 Series Selection Guide

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Features Beneﬁts

24Vac, 120Vac, and 230Vac models. Satisﬁes a wide range of power requirements.

Compact size. Allows installation in limited spaces.

Spring return. Valve returns to known position upon loss of power.

Manual override. Allows valve positioning and preload adjustment, simplifying installation,

start-up, and troubleshooting.

Rugged polymer or die-cast housings rated for up to NEMA2, UL Type2 (IP54).

Valve sizes 1/2” to 4” and 15 mm to 80 mm (Union Straightway, NPT, Flanged, Metric) 2-Way and 3-Way.

Up to 250 psig (1724 kPa) close-off. Meets variety of close-off requirements.

Built-in position feedback on MFx1-710x ﬂoating and all proportional models.

High ﬂuid and ambient temperature ratings. Allows use in harsh environments.

Proportional models feature control function switch or jumper. Allows the selection of direct or reverse action for application ﬂexibility.

Thermal isolation. Protects the actuator from cold or excess heat generated by chilled water,

Spring-loaded PTFE valve packing. Self adjusting. No tightening required.

250 psig valve body static pressure rating per ANSI Standards (B16.15—1985) for screwed cast bronze bodies. 125psig valve body static pressure rating for cast iron ﬂanged bodies.

Overload protection on all models. Eliminates application of excessive force on stem and overheating of

Highly visible position indicator. Shows the valve position, facilitating setup, checkout, and troubleshooting.

24Vac models require less than 10VA. Saves cost while meeting job speciﬁcations, by using fewer transformers

Water-resistant rating supports use in most common indoor HVAC environments.

Satisﬁes a wide range of application requirements.

Offers maximum ﬂexibility in selecting precise control for a wide variety of applications, signiﬁcantly reducing installation time.

hot water, or steam passing through the valve. Discourages condensation.

Meets most demanding pressure requirements.

actuator.

and less energy.

Selection Guide

Globe Valve Assembly Selection Procedure

When selecting a globe valve assembly, you must determine the applicable codes for the control signal type, valve body conﬁguration, end connection, port size, and actuator. Select a globe valve assembly part number as follows:

1. Control Signal Type, Valve Body Conﬁguration, and End Connection

Referring to “Part Numbering System” on page 4, select the appropriate codes for these part number elds.

2. Valve Size (Flow Coefﬁcient)

If the required ow coefcient (C

a. Refer to the “Sizing and Selection” section on pages 8 to 11, to calculate the required Cv.

b. Select the nearest available Cv and corresponding valve body port code from “Part Numbering System” on page 4.

3. Actuator

Select the appropriate actuator and code, according to “Part Numbering System” on page 4, based on the control signal type, required valve normal position, and voltage requirements. For detailed actuator information, refer to the applicable actuator specications on page 16, 19, or 21.

Note: Globe Valve Assemblies are not available with Mx51‑7103‑0x0 actuators (equipped with appliance wire). However, if

required, you may eld-assemble one of these actuators to a globe valve body. For information on Mx51-7103-0x0 actuators, refer to page 16.

4. Close-off Pressure

Conrm in Table-3 or Table-4 that the selected actuator and valve body combination provides sufcient close-off pressure. If no

close‑off pressure is shown, the valve body/actuator combination is not valid.

5. Available Space

If available space is a consideration, check the appropriate dimensional gure (Figure 8 through Figure 19) and its accompanying table for any potential t problems.

) has not yet been determined, do so as follows:

Selection Guide

Close-off Ratings

Nominal actuator close-off ratings are based on ANSI IV (0.01% leakage) with EPDM discs and PTFE discs in steam applications.

Metal-to-metal trim such as brass 3-way and high temperature stainless are designed for ANSI III (0.1% leakage). Seat leakage for reduced port versions of metal-to-metal seats may match the full port versions,

allowing up to 1% on the 0.4C

plugs.

Installation Considerations

Mounting Angle of Valve Assembly

Be sure to allow the necessary clearance around the valve assembly. The valve assembly must be mounted so that the valve stem is at least 5° above the horizontal. This ensures that any condensate that forms on the valve body will not travel into the linkage or actuator, where it may cause corrosion. On steam applications, where the ambient temperature approaches the limit of the actuator, the valve assembly must be mounted 45° from vertical. See the applicable Actuator General Instructions for details.

Insulation of Linked Globe Valve Assembly

The globe valve should be completely insulated to minimize the effect of heat transfer and condensation at the actuator.

Caution: The actuator and the integral linkage must not be insulated. Doing so will result in excess heat or condensation within the actuator.

Temperature Limits for Globe Valve Assembly

When installing the globe valve assembly, observe the minimum and maximum temperature limits given in the Actuator Speciﬁcations and

Valve Assembly Mounting Dimensions

section of this document.

Sizing and Selection

Flow Coefﬁcient (Cv)

Two-position Control

Two-position control valves are normally selected “line size” to keep pressure drop at a minimum. If it is desirable to reduce the valve below

line size, then 10% of “available pressure” (that is, the pump pressure differential available between supply and return mains with design ﬂow at the valve location) is normally used to select the valve.

Proportional Control

Proportional control valves are usually selected to take a pressure drop equal to at least 50% of the “available pressure.” As “available

pressure” is often difﬁcult to calculate, the normal procedure is to select the valve using a pressure drop at least equal to the drop in the coil or other load being controlled (except where small booster pumps are used) with a minimum recommended pressure drop of 5 psi (34 kPa). When the design temperature drop is less than 60°F (33°C) for conventional heating systems, higher pressure drops across the valve are needed for good results (Table-2).

Table 2. Conventional Heating System

Design Temperature Load Drop °F (°C)

60 (33) or More 50% 1 x Load Drop

40 (22) 66% 2 x Load Drop

20 (11) 75% 3 x Load Drop

a - Recommended minimum pressure drop = 5 psi (34 kPa).

Secondary Circuits with Small Booster Pumps: 50% of available pressure difference (equal to the drop through load, or 50% of booster pump head).

Recommended Pressure Drop (% of Available Pressure)

Multiplier on Load Drop

When sizing a valve, you must select a ﬂow coefﬁcient (Cv), which is

deﬁned as the ﬂow rate in gallons per minute (GPM) of 60°F water that will pass through the fully open valve with a 1psi pressure drop (ΔP) It is calculated according to this formula:

where ΔP is measured in psi.

Since the ﬂow rate through the heat exchanger is usually speciﬁed, the only variable normally available in sizing a valve is the pressure drop. The following information in this section can be used to determine what pressure drop to use in calculating a valve Cv. Once you have calculated the Cv, consult “Part Numbering System” on page 4 to select the valve body having the nearest available Cv.

Note: Metric equivalent.

The metric measure of ﬂow coefﬁcient is kvs, which is calculated according to the formula: kvs=

(where DP is measured in bar; 1 bar = 100 kPa.).

If the Cv is already known, it may be converted directly to its kvs equivalent: kvs=

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