Yokogawa MLX Operating Manual

User’s Manual

Model MLX Loop Powered Process Indicator

IM 60A02S01-01E-A

Edition

Page 2 of 28

Contents

Loop Powered Process Indicator ............................................................................................ 1

Contents .......................................................................................................................................................... 2

1. Introduction ............................................................................................................................................... 3

■ Regarding This Manual ........................................................................................................ 3

1.1 Safe Use of This Product ........................................................................................................ 4

1.2 Warranty ............................................................................................................................... 5

2. Handling Cautions ..................................................................................................................................... 6

2.1 Model and Specifications Check ............................................................................................. 7

2.2 Unpacking ............................................................................................................................. 7

2.3 Storage .................................................................................................................................. 7

2.4 Selecting the Installation Location .......................................................................................... 7

2.5 Insulation Resistance and Dielectric Strength Test .................................................................. 8

2.6 Installation of an Explosion-Protected Instrument .................................................................. 9

2.6.1 Factory Mutual (FM) Certification .................................................................................. 9

2.7 EMC Conformity Standards ............................................................................................. 10

3. Installation .............................................................................................................................................. 11

3.1 Mounting Examples ............................................................................................................. 12

4. Wiring ....................................................................................................................................................... 13

4.1 Wiring Precautions .............................................................................................................. 13

4.2 Selecting the Wiring Materials ............................................................................................. 13

4.3 Wiring ................................................................................................................................. 13

4.3.1 Loop Configuration ....................................................................................................... 13

5. Operation .................................................................................................. Error! Bookmark not defined.

5.1 Overview ................................................................................ Error! Bookmark not defined.

6. Maintenance ............................................................................................................................................. 22

6.1 Overview ............................................................................................................................. 22

6.2 Calibration Instruments Selection ........................................................................................ 22

6.3 Calibration .......................................................................................................................... 22

6.4 Rotating Display Direction ................................................................................................... 23

6.5 Cleaning .............................................................................................................................. 23

7. General Specifications ............................................................................................................................. 24

7.1 Standard Specifications ........................................................................................................ 24

7.2 Model and Suffix Codes ....................................................................................................... 25

7.5 Dimensions .......................................................................................................................... 27

Revision Record ........................................................................................................................................... 28

IM 60A02S01-01E-A

Page 3 of 28

1. Introduction

Thank you for purchasing the Model MLX Loop Powered Process Indicator. Your Model MLX Process Indicator was precisely calibrated at the factory before shipment. To ensure both safety and efficiency, please read this manual carefully before you operate the instrument.

The Model MLX field mounted indicator receives DC current signals from electronic transmitters and indicates process measurement values. This instruction manual gives instructions on handling, mounting, and wiring of the indicator.

■ Regarding This Manual

• This manual should be provided to the end user.

• The contents of this manual are subject to change without prior notice.

written permission.

• Yokogawa makes no warranty of any kind with regard to this manual, including, but not limited to,

implied warranty of merchantability and fitness for a particular purpose.

• If any question arises or errors are found, or if any information is missing from this manual, please

inform the nearest Yokogawa sales office.

• The specifications covered by this manual are limited to those for the standard type under the

specified model number break-down and do not cover custom-made instruments.

• Please note that changes in the specifications, construction, or component parts of the instrument

may not immediately be reflected in this manual at the time of change, provided that postponement of revisions will not cause difficulty to the user from a functional or performance standpoint.

• Yokogawa assumes no responsibilities for this product except as stated in the warranty.

• If the customer or any third party is harmed by the use of this product, Yokogawa assumes no

responsibility for any such harm owing to any defects in the product which were not predictable, or for any indirect damages.

• The following safety symbols are used in this manual:

WARNING

Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury.

IM 60A02S01-01E-A

Page 4 of 28

CAUTION

Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury. It

may also be used to alert against unsafe practices.

IMPORTANT

Indicates that operating the hardware or software in this manner may damage it or lead to system failure.

NOTE

Draws attention to information essential for understanding the operation and features.

1.1 Safe Use of This Product

For the safety of the operator and to protect the instrument and the system, please be sure to follow this manual’s safety instructions when handling this instrument. If these instructions are not heeded, the protection provided by this instrument may be impaired. In this case, Yokogawa cannot guarantee that the instrument can be safely operated. Please pay special attention to the following points:

(a) Installation

• This instrument may only be installed by an engineer or technician who has an expert knowledge of

this device. Operators are not allowed to carry out installation unless they meet this condition.

• All installation shall comply with local installation requirements and the local electrical code.

(b) Wiring

• The instrument must be installed by an engineer or technician who has an expert knowledge of this

instrument. Operators are not permitted to carry out wiring unless they meet this condition.

• Before connecting the power cables, please confirm that there is no current flowing through the

cables and that the power supply to the instrument is switched off.

• Do not open the covers when an explosive atmosphere is present.

(d) Maintenance

• Please carry out only the maintenance procedures described in this manual. If you require further

assistance, please contact the nearest Yokogawa office.

• Care should be taken to prevent the build up of dust or other materials on the display glass and the

name plate.

(e) Modification

IM 60A02S01-01E-A

Page 5 of 28

• Yokogawa will not be liable for malfunctions or damage resulting from any modification made to

this instrument by the customer.

1.2 Warranty

• The warranty shall cover the period noted on the quotation presented to the purchaser at the time of

purchase. Problems occurring during the warranty period shall basically be repaired free of charge.

• If any problems are experienced with this instrument, the customer should contact the Yokogawa

representative from which this instrument was purchased or the nearest Yokogawa office.

• If a problem arises with this instrument, please inform us of the nature of the problem and the

circumstances under which it developed, including the model specification and serial number. Any diagrams, data and other information you can include in your communication will also be helpful.

• The party responsible for the cost of fixing the problem shall be determined by Yokogawa

following an investigation conducted by Yokogawa.

• The purchaser shall bear the responsibility for repair costs, even during the warranty period, if the

malfunction is due to:

− Improper and/or inadequate maintenance by the purchaser.

− Malfunction or damage due to a failure to handle, use, or store the instrument in accordance

with the design specifications.

− Use of the product in question in a location not conforming to the standards specified by

Yokogawa, or due to improper maintenance of the installation location.

− Failure or damage due to modification or repair by any party except Yokogawa or an approved

representative of Yokogawa.

− Malfunction or damage from improper relocation of the product in question after delivery.

− Reason of force majeure such as fires, earthquakes, storms/floods, thunder/lightening, or other

natural disasters, or disturbances, riots, warfare, or radioactive contamination.

IM 60A02S01-01E-A

Page 6 of 28

2. Handling Cautions

This chapter provides important information on how to handle the MLX Loop Powered Process Indicator. Read this carefully before using the indicator.

The MLX indicator is thoroughly tested at the factory before shipment. When taking delivery of an instrument, visually check it to make sure that no damage occurred during shipment.

Also check that the indicator mounting hardware shown in figure 2.1 is included. After checking the indicator, carefully repack it in its box and keep it there until you are ready to install it.

Figure 2.1 MLX Mounting Hardware

IM 60A02S01-01E-A

Page 7 of 28

2.1 Model and Specifications Check

The model name and specifications are written on the name plate attached to the case.

MODEL: Specified model code. SUFFIX: Specified suffix code. MFG: Year of manufacture. NO.: Serial number. INPUT: Input signal (4-20mA).

CALIB RANGE: Specified calibration range.

Figure 2.2 MLX Name Plate

2.2 Unpacking

Keep the indicator in its original packaging to prevent it from being damaged during shipment. Do not unpack the indicator until it reaches the installation site.

2.3 Storage

The following precautions must be observed when storing the instrument, especially for a long period.

(a) Select a storage area which meets the following conditions:

• It is not exposed to rain or subject to water seepage/leaks.

• Vibration and shock are kept to a minimum.

• It has an ambient temperature and relative humidity within the following ranges.

Ambient temperature: –40 to 85°C (approval codes may affect limits) Relative humidity: 0% to 100% R.H. Preferred temperature and humidity: approx. 25°C and 65% R.H.

(b) When storing the indicator, repack it carefully in the packaging that it was originally shipped with.

2.4 Selecting the Installation Location

(1) The MLX is designed to withstand severe environmental conditions. However, to ensure that it will

provide years of stable and accurate performance, take the following precautions when selecting the installation location.

(2) Ambient Temperature

IM 60A02S01-01E-A

Page 8 of 28

(3) Avoid locations subject to wide temperature variations or a significant temperature gradient. If the

location is exposed to radiant heat from plant equipment, provide adequate thermal insulation and/or ventilation.

(4) Ambient Atmosphere (5) Do not install the indicator in a corrosive atmosphere. If this cannot be avoided, there must be

adequate ventilation as well as measures to prevent the leaking of rain water and the presence of standing water in the conduits.

(6) Shock and Vibration (7) Although the MLX is designed to be relatively resistant to shock and vibration, an installation site

should be selected where this is kept to a minimum.

2.5 Insulation Resistance and Dielectric Strength Test

Since the MLX has undergone insulation resistance and dielectric strength tests at the factory before shipment, normally these tests are not required. If the need arises to conduct these tests, heed the following:

(1) Do not perform such tests more frequently than is absolutely necessary. Even test voltages that do

not cause visible damage to the insulation may degrade the insulation and reduce safety margins.

(2) Never apply a voltage exceeding 500 V DC (100 V DC with an internal lightning protector) for the

insulation resistance test, nor a voltage exceeding 500 V AC (100 V AC with an internal lightning protector) for the dielectric strength test.

(3) Before conducting these tests, disconnect all signal lines from the transmitter terminals. The

procedure for conducting these tests is as follows:

• Insulation Resistance Test

(1) Short-circuit the + and – SUPPLY terminals in the terminal box. (2) Turn OFF the insulation tester. Then connect the insulation tester plus (+) lead wire to the

shorted SUPPLY terminals and the minus (–) lead wire to the grounding terminal.

(3) Turn ON the insulation tester power and measure the insulation resistance. The voltage

should be applied as briefly as possible to verify that the insulation resistance is at least 20 MΩ.

(4) After completing the test and being very careful not to touch exposed conductors disconnect

the insulation tester and connect a 100 kΩ resistor between the grounding terminal and the short-circuiting SUPPLY terminals. Leave this resistor connected at least one second to discharge any static potential. Do not touch the terminals while it is discharging.

• Dielectric Strength Test

(1) Short-circuit the + and – SUPPLY terminals in the terminal box. (2) Turn OFF the dielectric strength tester. Then connect the tester between the shorted

SUPPLY terminals and the grounding terminal. Be sure to connect the grounding lead of the dielectric strength tester to the ground terminal.

(3) Set the current limit on the dielectric strength tester to 10mA, then turn ON the power and

gradually increase the test voltage from ‘0’ to the specified voltage.

(4) When the specified voltage is reached, hold it for one minute. (5) After completing this test, slowly decrease the voltage to avoid any voltage surges.

IM 60A02S01-01E-A

Page 9 of 28

2.6 Installation of an Explosion-Protected Instrument

WARNING

If a customer makes a repair or modification and the instrument is not restored to its original condition, its safety may be compromised and the instrument may be hazardous to operate. Please contact Yokogawa before making any repair or modification to an instrument.

CAUTION

This instrument has been tested and certified as being Explosionproof. Please note that severe restrictions apply to this instrument’s construction, installation, external wiring, maintenance and repair. A failure to abide by these restrictions could make the instrument a hazard to operate.

WARNING

Maintaining the safety of Explosionproof equipment requires great care during mounting, wiring, and piping. Safety requirements also place restrictions on maintenance and repair. Please read the following sections very carefully.

2.6.1 Factory Mutual (FM) Certification

1) Technical Data

a. FM Explosionproof Type

Caution for FM Explosionproof type.

Note 1. Model MLX Loop Process Indicator with optional code /FF1 for potentially explosive atmospheres:

• Certificate No. 4000798

• Applicable Standard: FM 3600, FM 3615, FM 3810, NEMA 250

• Explosionproof for Class I, Division 1, Groups A, B, C, and D.

• Dust-ignitionproof for Class II/III, Division 1, Groups E, F and G.

• Enclosure rating: NEMA 4X.

• Temperature Class: T5

• Ambient Temperature: –30 to 60°C

Note 2. Wiring

• All wiring shall comply with National Electrical Code ANSI/NEPA70 and Local Electrical Codes.

• “FACTORY SEALED, CONDUIT SEAL NOT REQUIRED”.

IM 60A02S01-01E-A

+ 19 hidden pages