WATLOWEZ-ZONE® PMUser’s GuidePID Controller Models

Safety Information

We use note, caution and warning symbols throughout this book to draw your attention to 

important operational and safety information.

• A “NOTE” marks a short message to alert you to an important detail.

• A “CAUTION” safety alert appears with information that is important for protecting your 

equipment and performance. Be especially careful to read and follow all cautions that 

apply to your application.

• A “WARNING” safety alert appears with information that is important for protecting you, 

others and equipment from damage. Pay very close attention to all warnings that apply 

to your application.

• The electrical hazard symbol, Ó (a lightning bolt in a triangle) precedes an electric 

shock hazard CAUTION or WARNING safety statement.

Symbol Explanation

CAUTION – Warning or Hazard that needs further explanation than label on 

unit can provide. Consult User's Guide for further information.

ESD Sensitive product, use proper grounding and handling techniques 

when installing or servicing product.

Unit protected by double/reinforced insulation for shock hazard prevention.

Do not throw in trash, use proper recycling techniques or consult manufacturer for proper disposal.

Enclosure made of Polycarbonate material. Use proper recycling techniques or consult manufacturer for proper disposal.

Unit can be powered with either alternating current (ac) voltage or direct 

current (dc) voltage.

Unit is a Listed device per Underwriters Laboratories®. It has been evaluated to United States and Canadian requirements for Process Control 

Equipment. UL 61010 and CSA C22.2 No. 61010. File E185611 QUYX, 

QUYX7. See: www.ul.com

Unit is a Listed device per Underwriters Laboratories®. It has been evaluated to United States and Canadian requirements for Hazardous Locations 

Class 1 Division II Groups A, B, C and D. ANSI/ISA 12.12.01-2007. File 

E184390 QUZW, QUZW7. See: www.ul.com

Unit is compliant with European Union directives. See Declaration of 

Conformity for further details on Directives and Standards used for 

Compliance.

Warranty

The EZ-ZONE® PM is manufactured by ISO 9001-registered processes and is backed by a 

three-year warranty to the first purchaser for use, providing that the units have not been 

misapplied. Since Watlow has no control over their use, and sometimes misuse, we cannot guarantee against failure. Watlow’s obligations hereunder, at Watlow’s option, are limited to replacement, repair or refund of purchase price, and parts which upon examination 

prove to be defective within the warranty period specified. This warranty does not apply to 

damage resulting from transportation, alteration, misuse or abuse. The purchaser must use 

Watlow parts to maintain all listed ratings.

Technical Assistance

If you encounter a problem with your Watlow controller, review your configuration information to verify that your selections are consistent with your application: inputs, outputs, 

alarms, limits, etc. If the problem persists, you can get technical assistance from your local 

Watlow representative (see back cover), by e-mailing your questions to wintechsupport@watlow.com or by dialing +1 (507) 494-5656 between 7 a.m. and 5 p.m., Central Standard Time 

(CST). Ask for for an Applications Engineer. Please have the following information available 

when calling:

• Complete model number 

• All configuration information

• User's Guide 

• Factory Page

Return Material Authorization (RMA)

1. Call Watlow Customer Service, (507) 454-5300, for a Return Material Authorization (RMA) 

number before returning any item for repair. If you do not know why the product failed, 

contact an Application Engineer or Product Manager. All RMA’s require:

• Ship-to address

• Bill-to address

• Contact name 

• Phone number

• Method of return shipment

• Your P.O. number

• Detailed description of the problem 

• Any special instructions

• Name and phone number of person returning the product.

2. Prior approval and an Return Merchandise Authorization number from the Customer 

Service Department is required when returning any product for credit, repair or evaluation. Make sure the Return Merchandise Authorization number is on the outside of the 

carton and on all paperwork returned. Ship on a Freight Prepaid basis.

3. After we receive your return, we will examine it and try to verify the reason for returning it.

4. In cases of manufacturing defect, we will enter a repair order, replacement order or 

issue credit for material returned. In cases of customer misuse, we will provide repair 

costs and request a purchase order to proceed with the repair work.

5. To return products that are not defective, goods must be in new condition, in the original boxes and they must be returned within 120 days of receipt. A 20 percent restocking 

charge is applied for all returned stock controls and accessories.

6. If the unit cannot be repaired, you will receive a letter of explanation and be given the 

option to have the unit returned to you at your expense or to have us scrap the unit.

7. Watlow reserves the right to charge for no trouble found (NTF) returns.

This EZ-ZONE® PM User’s Guide is copyrighted by Watlow Electric, Inc., © August 2016 with 

all rights reserved. 

EZ-ZONE PM is covered by U.S. Patent Numbers: 6005577; D553095; D553096; D553097; 

D560175; D55766; and OTHER PATENTS PENDING

Chapter 1: Overview 1

Available EZ-ZONE PM Literature and Resources

The DVD described above ships with the product and as stated contains all of the literature 

above as well as much more. If the DVD is not available one can be acquired by contacting 

Watlow Customer Service at 1-507-454-5300.

As an alternative to the DVD, all of the user documentation described above can also be 

found on the Watlow website. Click on the following link to find your document of choice: 

http://www.watlow.com/literature/index.cfm. Once there, simply type in the desired part 

number (or name) into the search box and download free copies. Printed versions of all user 

documents can also be purchased here as well.

Your Comments are Appreciated

In an effort to continually improve our technical literature and ensure that we are providing 

information that is useful to you, we would very much appreciate your comments and suggestions. Please send any comments you may have to the following e-mail address: 

TechlitComments@watlow.com

Introduction

The EZ-ZONE® PM takes the pain out of solving your thermal loop requirements. Watlow’s 

EZ-ZONE PM controllers offer options to reduce system complexity and the cost of control 

loop ownership. You can order the EZ-ZONE PM as a PID controller or an over-under limit 

controller, or you can combine both functions in the PM Integrated Controller. You now have 

the option to integrate a high-amperage power controller output, an over-under limit controller and a high-performance PID controller all in space saving, panel-mount packages. You 

can also select from a number of industrial serial communications options to help you manage system performance.

Standard Features and Benefits

Advanced PID Control Algorithm

• TRU-TUNE+® Adaptive tune provides tighter control for demanding applications.

• Auto Tune for fast, efficient start ups

High-amperage Power Control Output

• Drives 15 amp resistive loads directly

• Reduces component count

• Saves panel space and simplifies wiring

• Reduces the cost of ownership

EZ-ZONE configuration communications and software

• Saves time and improves the reliability of controller set up

Parameter Save & Restore Memory

• Reduces service calls and down time

Agency approvals: UL Listed, CSA, CE, RoHS, W.E.E.E. FM

• Assures prompt product acceptance

• Reduces end product documentation costs

• Semi F47-0200

P3T Armor Sealing System

• NEMA 4X and IP65 offers water and dust resistance, can be cleaned and washed down (indoor use only)

• Backed up by UL 50 independent certification to NEMA 4X specification

Three-year warranty

• Demonstrates Watlow’s reliability and product support

Touch-safe Package

• IP2X increased safety for installers and operators

Removable cage clamp wiring connectors 

• Reliable wiring, reduced service calls

• Simplified installation 

EZ-Key/s 

• Programmable EZ-Key enables simple one-touch operation of repetitive user activities

Programmable Menu System

• Reduces set up time and increases operator efficiency 

Full-featured Alarms

• Improves operator recognition of system faults

• Control of auxiliary devices

Heat-Cool Operation 

• Provides application flexibility with accurate temperature and process control 

Profile Capability

• Pre-programmed process control

• Ramp and soak programming with four files and 40 total steps

Getting Started Quickly

The PM control has a page and menu structure that is listed below along with a brief description of its purpose.

The default PM loop configuration from the factory is shown below: 

• Analog Input functions set to thermocouple, type J

• Heat algorithm set for PID, Cool set to off

• Output 1 set to Heat

• Control mode set to Auto

• Set point set to 75 °F

If you are using the input type shown above, simply connect your input and output devices 

to the control. Power up the control and push the up arrow ¿ on the face of the control to 

change the set point from the default value of 75°F to the desired value. As the Set Point 

increases above the Process Value, output 1 will come on and it will now begin driving your 

output device. The PV function as shown in the graphic below is only available with PM4/8/9 

models. 

Note: 

The output cycle time will have a bearing on the life of mechanical relay outputs and can 

be different based on the type of output ordered. The output cycle time can be changed 

in the Setup Page under the Output Menu.

A Conceptual View of the PM

The flexibility of the PM’s software and hardware allows a large range of configurations. Acquiring a better understanding of the controller’s overall functionality and capabilities while 

at the same time planning out how the controller can be used will deliver maximum effectiveness in your application.

It is useful to think of the controller in three parts: inputs; procedures; and outputs. Information flows from an input to a procedure to an output when the controller is properly 

configured. A single PM controller can carry out several procedures at the same time, for 

instance closed-loop control, monitoring for several different alarm situations and operating 

switched devices, such as lights and motors. Each process needs to be thought out carefully 

and the controller’s inputs, procedures and outputs set up properly.

Inputs

The inputs provide the information that any given programmed procedure can act upon. In a 

simple form, this information may come from an operator pushing a button or from a sensor 

monitoring the temperature of a part being heated or cooled.

Each analog input typically uses a thermocouple or RTD to read the process temperature. It 

can also read volts, current or resistance, allowing it to use various devices to read a wide 

array of values.

A PM with digital input/output (DIO) hardware includes two sets of terminals where each of 

which can be used as either an input or an output. Each pair of terminals must be configured 

to function as either an input or output with the direction parameter in the Digital Input/

Output Menu (Setup Page). Each digital input reads whether a device is active or inactive. 

The Function or EZ Key/s (PM4/6/8/9 only) on the front panel of the PM also operates as a 

digital input by toggling the function assigned to it in the Digital Input Function parameter in 

the Function Key Menu (Setup Page).

Internal Functions

The controller will use input signals to calculate a value and then perform an operation. A 

sample of some functions may be as simple as:

• Compare an input value to the set point and calculate the optimal power for a heater

• Detect a failure of the primary sensing device and trip a contactor to remove power from 

the heating element

• Reading a digital input to set a state to true or false

• Evaluate an incoming temperature to determine an alarm state (on or off)

To set up a function, it’s important to define the source, or instance, to use. For example, if 

the control is equipped with DIO they can be configured to respond to an alarm. If configured 

as such, the digital output must be tied to the desired alarm instance (1 to 4). Using this as 

an example, the Function for the digital output would be defined as an Alarm where the Instance would be selected as 1, 2, 3, or 4 corresponding to the alarm instance that will drive 

the output.

Keep in mind that a function is a user-programmed internal process that does not execute 

any action outside of the controller. To have any effect outside of the controller, an output 

must be configured to respond to a function..

Outputs

Outputs can perform various functions or actions in response to information provided by a 

function such as, removal of the control voltage to a contactor; operating a heater, turning a 

light on or off, unlocking a door, etc...

Assign a Function to any available output on the Setup Page within the Output Menu or Digital Input/Output Menu. Then select which instance of that function will drive the selected 

output. For example, you might assign an output to respond to alarm 4 (instance 4).

You can assign more than one output to respond to a single instance of a function. For example, alarm 2 could be used to trigger a light connected to output 1 and a siren connected 

to digital output 5.

Input Events and Output Events

Input and output events are internal states that are used exclusively by profiles. The source 

of an event input can come from a real-world digital input or an output from another function. Likewise, event outputs may control a physical output such as an output function block 

or be used as an input to another function.

What is a Profile

A profile is a set of instructions consisting of a sequence of steps. When a profile runs, the 

controller automatically executes its steps in sequence. The step type determines what action the controller performs. Steps can change temperatures and other process values gradually over time, maintain the temperatures and process values for specific periods, or repeat 

a sequence of steps numerous times. At each step the profile can activate or deactivate 

outputs that control other equipment. Also a step can have the controller wait for specific 

conditions before proceeding such as, waiting for a switch closure and/or a specific process 

value to be detected by a sensor.

EZ-ZONE® PM PID Model System Diagram

Universal Sensor Input, Configuration Communications,

Red/Green 7-Segment Display

Chapter 2: Install and Wire

Installation

1. Make the panel cutout using the mounting template dimensions in this chapter. Insert the 

case assembly into the panel cutout.

2. While pressing the case assembly firmly 

against the panel, slide the mounting collar 

over the back of the controller.

Note:

If the installation does not require a NEMA 4X 

seal, simply slide together until the gasket is 

compressed.

3. For a NEMA 4X (UL50, IP65) seal, alternately 

place and push the blade of a screwdriver 

against each of the four corners of the mounting collar assembly. Apply pressure to the face 

of the controller while pushing with the screwdriver. Don't be afraid to apply enough 

pressure to properly install the controller. The seal system is compressed more by mating 

the mounting collar tighter to the front panel (see pictures above). If you can move the 

case assembly back and forth in the cutout, you do not have a proper seal.

The tabs on each side of the mounting collar have teeth that latch into the ridges on the 

sides of the controller. Each tooth is staggered at a different depth from the front so that 

only one of the tabs, on each side, is locked onto the ridges at a time.

Note: 

There is a graduated measurement difference between the upper and lower half of the 

display to the panel. In order to meet the seal requirements mentioned above, ensure 

that the distance from the front of the top half of the display to the panel is 16 mm 

(0.630 in.) or less, and the distance from the front of the bottom half and the panel is 

13.3 mm (0.525 in.) or less.

Removing the Mounted Controller from Its Case

1. From the controller's face, pull out the tabs on each side until you hear it click

2. 

2. On a PM6 control once the sides are released grab the unit above and below the face with 

two hands and pull the unit out. On the PM4/8/9 controls slide a screwdriver under the 

pry tabs and turn.

WARNING! ç

• This equipment is suitable for use in class 1, div. 2, Groups A, B, C and D or Non-Hazardous 

locations only. Temperature Code T4A.

• WARNING – EXPLOSION HAZARD. Substitution of component may impair suitability for class 1, 

div. 2.

• WARNING – EXPLOSION HAZARD. Do not disconnect equipment unless power has been 

switched off or the area is known to be nonhazardous.

Returning the Controller to its Case

1. Ensure that the orientation of the controller is correct and slide it back into the housing.

Note:

The controller is keyed so if it feels that it will not slide back in do not force it. Check the 

orientation again and reinsert after correcting.

2. Using your thumbs push on either side of the controller until both latches click.

Chemical Compatibility

This product is compatible with acids, weak alkalis, alcohols, gamma radiation and ultraviolet radiation. This product is not compatible with strong alkalis, organic solvents, fuels, 

aromatic hydrocarbons, chlorinated hydrocarbons, esters and keytones.

WARNING! ç

All electrical power to the controller and controlled circuits must be disconnected before 

removing the controller from the front panel or disconnecting other wiring. Failure to follow 

these instructions may cause an electrical shock and/or sparks that could cause an explosion 

in class 1, div. 2 hazardous locations.

Default Home Page Parameters

Watlow's patented user-defined menu system improves operational efficiency. The userdefined Home Page provides you with a shortcut to monitor or change the parameter values 

that you use most often. The default Home Page is shown on the following page. When a parameter normally located in the Setup Page or Operations Page is placed in the Home Page, 

it is accessible through both. If you change a parameter in the Home Page, it is automatically 

changed in its original page. If you change a parameter in its original page it is automatically 

changed in the Home Page. 

Use the Advance Key ‰ to step through the other parameters. When not in pairs, the parameter prompt will appear in the lower display, and the parameter value will appear in the 

upper display. You can use the Up ¿ and Down ¯ keys to change the value of writable parameters, just as you would in any other menu.

Note:

If a writable value is placed on the upper display and is paired with another read only 

parameter on the lower display, the arrow keys affect the setting of the upper display. If 

two writable parameters are paired, the arrow keys affect the lower display.

• The Attention attn parameter appears only if there is an active message. An example of 

an active message could be a Input Error Er.i1, or it could be for information only like 

Autotune tUn1 taking place.

• If Control Mode is set to Auto, the Process Value is in the upper display and the Set Point 

(read-write) is in the lower display.

• If a profile is running, the process value is in the upper display and the Target Set Point 

(read only) is in the lower display. If Control Mode is set to Manual, the Process Value is in 

the upper display and Manual Power (read-write) is in the lower display.

• If Control Mode is set to Off, the Process Value is in the upper display and off (read only) 

is in the lower display.

• If a sensor failure has occurred, dashes ---- will be displayed in the upper display and 

the Manual Power (read-write) is in the lower display