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PRECAUTIONS AND W ARNINGS CONCERNING THE APPLICA TION, INSTALLA TION AND SERVICE OF MAC V ALVES AND OTHER MA C VALVES PRODUCTS The warnings and precautions below are important to be read and understood bef ore designing …

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Consult “Precautions” page 327 before use, installation or service of MAC Valves..

Technical Info

TWO WIRE

The two wire method shown in Figure 7, provides a black and red lead wire connected

to the solenoid. The user must provide the polarity switching circuitry to these leads in

order to shift the valve to its two positions. By applying positive DC voltage to the red

lead wire and negative to the black, the valve will be open to cylinder port “A”. When

the polarity of the voltage is externally reversed to the lead wires the valve will now

become open to cylinder port “B”.

AVAILABLE OPTIONS

The 2 and 4 wire connections are available in both a flying lead and plug-in cover. The 3 wire connection is only available in the plug-in style cover. All 2 and 4

wire cover options are available with an LED indicator. The LED indicator on a 3 wire cover is standard. The LED will illuminate red for cylinder “A” operation

and green for cylinder “B” operation.

The 3 wire connection must be used for valves connected to either a multi-pin connector or a serial manifold. Mixing single solenoids with latching solenoids on a

circuit bar is possible since each station of the bar is wired for a latching coil. The circuit bar must be ordered with this wiring configuration. If required, a

negative common 3 wire connection is also available, please consult factory.

HOW TO ORDER

The numbering system for a latching solenoid differs from the numbering system for a single solenoid valve. The letter “L” within the model number indicates a

latching solenoid, while the letter “G” or "H" in the same position of the model number indicates a single solenoid valve.

• No circuit board needed

• Customer must switch polarity of voltage

• Red to Positive and Black to Negative yields

flow to cylinder port A

• Red to Negative and Black to Positive yields

flow to cylinder port B

Red

Black

Figure 7 : Two Wire Latching

PRECAUTIONS AND WARNINGS

CONCERNING THE APPLICATION, INSTALLATION AND SERVICE OF MAC VALVES

AND OTHER MAC VALVES PRODUCTS

The warnings and precautions below are important to be read and understood before

designing into a system any MAC Valves products, and before installing or servicing any MAC Valves

product. Improper use, installation or servicing of any MAC Valves product in some systems could

create a hazard to personnel or equipment. No distinction in importance should be made between

the terms warnings and precautions.

WARNING : .

Under no circumstances are MAC Valves products to be used in any application or in any manner

wher

e failure of the MAC

Valves product to operate as intended could in any way jeopardize the

safety of the operator or any other person or property.

• Do not operate outside of pressure range listed on a valve label or outside of the designated

temperature range.

• Air supply must be clean and dry. Moisture or contamination can affect proper operation of the

valve.

• Before attempting to repair, adjust or clean a MAC Valves product, consult catalog, parts & operation

sheet, or factory for proper maintenance procedures, lubrication and cleaning agents. Never

attempt to repair or perform other maintenance with air pressure to the valve.

• If air line lubrication is used do not use any lubrication other than those recommended in the

catalog, parts & operation sheet or by the factory.

APPLICATION PRECAUTIONS : .

INDUSTRIAL USE -

•

MAC V

alve products are intended for general use in industrial pneumatic and/or vacuum systems.

They are general purpose industrial products with literally thousands of different applications in

industrial systems. These products are not inherently dangerous, but they are only a component of

an overall system. The system in which they are used must provide adequate safeguards to prevent

injury or damage in the event failure occurs, whether it be failure of switches, regulators, cylinders,

valves or any other component.

POWER PRESSES -

MAC Valve products are not designed nor intended to be used to operate and/or control the

operation of clutch and/or brake systems on power presses. There are special products on the market

for such use.

2-POSITION VALVES -

Some MAC valves are 2-position, 4-way valves. When air is supplied to the inlet port(s) of these valves,

there will always be a flow path from the inlet to one of the outlets regardless of which of the two

positions the valve is situated. Therefore, if pressurized air retained in the system would present a

hazard in the application or servicing of the valve or system, a separate method in the system must

be provided to remove the trapped air.

3- POSITION VALVES-

Some MAC valves are 3-position, 4-way valves. These valves are either double solenoid or double

remote air operated.

If either of the two operators is in control, air supplied to the inlet port(s) will pass through the valve

to one of the outlets as on 2-position, 4-way valves. However, if neither operator is in control, the

valve moves to a center position. Listed below are the various center position functions :

A. CLOSED CENTER-

With this type valve, when in the center position all ports are blocked (inlets and exhausts) meaning

the air at both outlet ports is trapped. If trapping the air in both outlet ports would present a hazard

in the application or servicing, a separate method in the system must be provided to remove the

trapped air or this type valve should not be used.

B. OPEN CENTER-

With this type valve, when in the center position, the inlet port(s) is blocked and the two outlet ports

are open to the exhaust port(s) of the valve. If having no air in either outlet port would present a

hazard in the application or servicing, this type valve should not be used.

C. PRESSURE CENTER-

With this type valve, when in the center position, the inlet port(s) is connected to both outlet ports of

the valve. If having pressurized air to either or both outlet ports would present a hazard in the

application or servicing of the valve or system, a separate method in the system must be

provided to remove the retained air or this type valve should not be used.

OPERATING SPECIFICATIONS -

MAC Valves products are to be installed only on applications that meet all operating specifications

described in the MAC catalog for the MAC Valves product.

MANUAL OPERATORS-

Most MAC valves can be ordered with manual operators. Manual operators when depressed, are

designed to shift the valve to the same position as would the corresponding solenoid or remote air

pilot operator if it were activated. Care must be taken to order a type, if any, that will be safe for the

physical location of the manual operator in the system. If intentional or accidental operation of a

valve by a manual operator could cause personal injury or property damage, a manual operator

should not be used.

REMOTE AIR OPERATED VALVES

Pilot valves supplying signal pressure to remote air operated valves should be 3-way valves with

adequate supply and exhaust capacity to provide positive pressurizing and exhausting of the pilot

supply line. Pilot lines should be open to exhaust when valves are deenergized.

INSTALLATION PRECAUTIONS : .

A. Do not install any MAC Valves product without first turning off air (bleed system completely) and

elec

tricity to the machine.

. MAC Valves products should only be installed by qualified, knowledgeable personnel who

understand how the specific valve is to be pneumatically piped and electrically connected (where

applicable). Flow paths through the valve are shown in the catalog and on the valve by use of ANSI

or ISO type standard graphic symbols. Do not install unless these symbols and the valve functions

and operations are thoroughly understood.

C. If air line lubrication is used do not use any lubrication other than those recommended in the

catalog, parts & operation sheet or by the factory.

SERVICE PRECAUTIONS :

A. Do not service or remove from service any MAC Valves product without first shutting off both the

air and electricity to the valve and making certain no pressurized air which could present a hazard

is retained in the system.

B. MAC Valves products should only be serviced or removed from service by qualified, knowledgeable

personnel who understand how the specific product is used and/or how the specific valve is piped

and used and whether there is air retained in the connecting lines to the valve or electric power still

connected to the valve.

C. Before attempting to repair, adjust or clean a MAC Valves product, consult catalog, parts &

operation sheet, or factory for proper maintenance procedures, lubrication and cleaning agents.

Never attempt to repair or perform other maintenance with air pressure to the valve.

D. MAC Valves products are never to be stepped on while working on a machine. Damage to a MAC

valve, or other product or lines to the product (either air or electrical lines) or accidental activation

of a manual operator on the valve could result in personal injury or property damage.

LIMITATION OF GUARANTEE .

This Guarantee is limited to the replacement or rebuilding of any valve or other product which should

fail t

o operate properly.

Valves or other products, under the MAC Guarantee, must be returned (with

or without bases) transportation prepaid and received at our factory within the Guarantee period.

They will be returned to the customer at the expense of MAC Valves, Inc., and will carry the same

guarantee as provided under the Flat Rate Rebuild Program.

DISCLAIMER OF GUARANTEE .

No claims for labor, material, time, damage, or transportation ar

e allowable nor will any valve or other

oduct be replaced or rebuilt under this guarantee which has been damaged by the purchaser not

in the normal course of its use and maintenance during the warranty period. The guarantee does not

apply to loss or damage caused by fire, theft, riot, explosion, labor dispute, act of God, or other causes

beyond the control of MAC Valves,Inc. MAC Valves, Inc. shall in no event be liable for remote, special

or consequential damages under the MAC Guarantee, nor under any implied warranties, including

the implied warranty of merchantability.

The above Guarantee is our manner of extending the engineering and service resources of the MAC

Valves, Inc. organization to assure our customer long, and continued satisfaction.

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MAC VALVES Warranty, Warranty Limitations, Flat Rate Rebuild Program

MAC Valves Product Warranty Information

The MAC Valves organization has established a reputation over many years for fulﬁlling the needs and requirements of the

users of its products. All MAC Valves are quality products speciﬁcally designed and built for long and rugged service. For

this reason, MAC Valves is able to provide the Buyer a limited warranty.

WARRANTY:

MAC Valves, Inc. hereby warrants to Buyer that, for a period of 18 months from the original date of shipment of each valve

from our factory (“Warranty Period”), such valve will be free from signiﬁcant defects in material and workmanship and will

conform to all speciﬁcations agreed to by MAC Valves, Inc.. In addition, MAC Valves, Inc. warrants that the electrical coils

on such valves will be free from signiﬁcant defects in material and workmanship for their normal useful life. EXCEPT FOR

THESE LIMITED WARRANTIES, MAC VALVES, INC. EXPRESSLY DISCLAIMS ALL REPRESENTATIONS AND WARRANTIES OF

ANY KIND (WHETHER EXPRESS, IMPLIED OR ARISING BY OPERATION OF LAW) WITH RESPECT TO THE VALVES,

INCLUDING, WITHOUT LIMITATION, ANY WARRANTIES OR REPRESENTATIONS AS TO MERCHANTABILITY, FITNESS FOR

A PARTICULAR PURPOSE OR ANY OTHER MATTER. THIS SECTION SURVIVES THE EXPIRATION, TERMINATION OR

CANCELLATION OF ANY AGREEMENTS BETWEEN THE PARTIES RELATING TO THE PURCHASE OF THE VALVES.

WARRANTY LIMITATIONS:

This Warranty does not apply where the valves have been (i) subjected to abuse, misuse, damage, neglect, negligence,

accident, improper testing, improper installation, improper storage, improper handling, abnormal physical stress, abnormal

environmental condition, or use contrary to any instructions issued by MAC Valves, Inc.; (ii) modiﬁed, reconstructed, repaired,

or altered by persons other than MAC Valves, Inc. or its authorized representative; or (iii) used with any third-party product,

hardware, software or other product that has not been previously approved in writing by MAC Valves, Inc. Additionally, this

Warranty does not cover claims for labor, material, time or transportation, and does not apply to loss or damage caused by

ﬁre, theft, riot, explosion, labor dispute, act of God, or other causes beyond the control of MAC Valves, Inc.

EXCLUSIVE REMEDY:

The Buyer’s sole remedy under this Warranty is limited to the replacement or rebuilding of any valve which does not conform

to the warranties provided herein or, in MAC Valves, Inc.’s sole discretion, refund of the purchase price for the non-conform-

ing valve. Buyer’s remedy is conditioned on Buyer’s compliance with its obligations under this Warranty. Valves that Buyer

believes do not conform to this Warranty must be returned (with or without bases) transportation prepaid and received at our

factory within the Warranty Period. If MAC Valves, Inc. determines that the valve is non-conforming and is otherwise covered

by this Warranty, the rebuilt or replaced valve will be returned to the customer at the expense of MAC Valves, Inc., and will

carry the same warranties as provided under the Flat Rate Rebuild Program described below. MAC VALVES, INC. WILL NOT

BE RESPONSIBLE FOR ANY INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES, INCLUDING WITHOUT

LIMITATION DIRECT AND INDIRECT LOST PROFITS, REGARDLESS OF WHETHER THOSE DAMAGES WERE FORESEEABLE.

THE FLAT REBUILD PROGRAM:

Valves no longer covered by the MAC Warranty may be eligible for a one-time rebuild under the MAC Valves, Inc. Flat Rate

Rebuild Program. Our constant research and testing program is dedicated to extending the life of our valves and maximizing

their reliability under the most adverse conditions. Valves returned under this limited program are completely disassembled,

inspected, rebuilt to current operating standards whenever possible, tested and returned within a few weeks for a nominal

ﬂat rate charge. All rebuilt valves carry the same warranty described (in our MAC Warranty) for new valves for a warranty

period of 90 days from the date of shipment from our factory.

Valves that have gone through the one-time rebuild will have been marked with a letter “R” as part of the date stamp (This is

an example of a rebuild date stamp from this month E(May)17(Year)Tester Symbol R(Indicates Rebuild).

Please note that any valves sent back for subsequent rebuild that have already been through the program previously

(indicated by the “R”) will not be eligible for additional rebuild.