3COM 59039-2 User Manual

-DIN DIGITAL INDICATOR

PRODUCT MANUAL

59039-2

PREFACE

This manual comprises two volumes:

Volume I: This supports normal operation of the

Digital Indicator. In normal operation, all actions taken by the user are to be in front of the panel.

Volume II: This supports the installation, commissioning and

configuring of the

-DIN Digital Indicator. It is

intended for use only by personnel who are trained, equipped and authorised to carry out these functions.

-DIN

CAUTION: REFER TO MANUAL

THE INTERNATIONAL HAZARD SYMBOL IS INSCRIBED ADJACENT TO

THE REAR CONNECTION TERMINALS. IT IS IMPORTANT TO READ THE

MANUAL BEFORE INSTALLING OR COMMISSIONING THE UNIT.

59039

-DIN Digi tal In di ca tor

Prod uct Man ual - Vol ume I

-DIN DIGITAL INDICATOR

PRODUCT MANUAL

VOLUME I

OPERATING INSTRUCTIONS

In normal operation, the operator must not remove the Indicator from its housing or have unrestricted access to the rear terminals, as this would provide potential contact with hazardous live parts.

Installation and configuration must be undertaken by technically competent servicing personnel. This is covered in Volume II of this manual.

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-DIN Digi tal In di ca tor 59039

Prod uct Man ual - Vol ume I

Con tents

1 IN TRO DUC TION 1-1 2 OP ERA TOR MODE 2-1 3 SET UP MODE 3-1 4 RS485 SE RIAL COM MU NI CA TIONS 4-1

Ap pen di ces

A Al pha beti cal In dex A-1

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-DIN Digi tal In di ca tor Sec tion 1

Prod uct Man ual - Vol ume I In tro duc tion

SEC TION 1

INTRODUCTION

The

-DIN Digital Indicator is an easy-to-operate microprocessor-based instrument,

incorporating the latest in surface-mount and CMOS technology. The standard features include:

Large four- digit LED dis play (or der able as red or green).

Dis play for units in di ca tion

Uni ver sal sen sor in put - ther mo cou ple, three- wire RTD or DC lin ear

(mA, mV or V) In put range se lected from the front panel.

Alarm 1 latch ing or non- latching (user- selectable) re lay out put

Alarm hys tere sis

Maxi mum Hold, Mini mum Hold and Time Elapsed fea tures.

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Sec tion 1 In tro duc tion Prod uct Man ual - Vol ume I

90 - 264V AC power sup ply.

De signed to com ply with EN50081 Part 2 (Emis sion) and EN50082

(Im mu nity) EMC speci fi ca tions. Front panel seal ing to IP65 (NEMA 4) stan dard.

Pro gram ma ble digi tal fil ter.

Proc ess Vari able off set fa cil ity

Alarm type se lected from front panel.

Sen sor Break in di ca tion.

and the many optional features include:

-DIN Digi tal In di ca tor 59039

Alarm 2 and Alarm 3 re lay out puts

Re mote re set of latched alarm

Re- transmitted Proc ess Vari able out put

Trans mit ter power sup ply

ASCII and MOD BUS com mu ni ca tions pro to cols

RS485 se rial com mu ni ca tions.

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Prod uct Man ual - Vol ume I Op era tor Mode

SEC TION 2

OPERATOR MODE

2.1 INTRODUCTION

The Operator Mode is the normal mode of the Indicator, once it has been set up and configured as required. The front panel displays, indicators and keys are shown in Figure 2-1.

Fig ure 2-1 Front Panel Con trols, Dis plays and In di ca tors

2.2 FOUR-DIGIT DISPLAY

In Operator Mode, this normally displays the process variable value. Using the Scroll key, the operator may view, in a sequence according to the Operator Mode Display Strategy parameter in Set Up Mode (see NOTES ON TABLE 3-1):

(i) Cur rent maxi mum value at tained by pro cess vari able (since the maxi mum value was last re set) - MAX in di ca tor ON when this is dis played. Also saves the Sen sor Break (see Sub sec tion 2.6) and Over- Range (see Sub sec tion

2.5) con di tions. (ii) Cur rent mini mum value at tained by pro cess vari able (since the mini mum

value was last re set) - MIN in di ca tor ON when this is dis played. Also saves the Sen sor Break (see Sub sec tion 2.6) and Under- Range (see Sub sec tion

2.5) con di tions.

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(iii) Time elapsed in the Alarm 1 ac tive con di tion (units dis play shows ). The dis play is in the for mat mm.ss [mm = min utes, ss = sec onds] or mmm.s [mmm = min utes, s = sec onds (tens)]. If elapsed time is greater than 999 min utes 59 sec onds, dis play will show:

NOTE: This does not in clude time when Alarm 1 is latched but alarm con di tion is cleared

(iv) Alarm 1 value (units dis play shows or, if only Alarm 1 pres ent, ). (v) Alarm 2 value, if fit ted and con fig ured (units dis play shows ). (vi) Alarm 3 value, if fit ted and con fig ured (units dis play shows ). (iv) Proc ess vari able value.

Further depressions of the Scroll key will repeat this display sequence.

2.3 ALARM STATUS INDICATORS

The Alarm Status indicators show the current state of the alarm(s):

AL1 - Flashes when Alarm 1 is ac tive (with latch ing alarm, ON when Alarm 1 is latched but alarm con di tion has cleared) AL2 - Flashes when Alarm 2 is ac tive AL3 - Flashes when Alarm 3 is ac tive

For descriptions of the operation of the various types of alarm available, see Section 3.

2.4 RESETTING THE MAXIMUM VALUE/MINIMUM VALUE OR TIME ELAPSED

VALUE

To reset the maximum value, minimum value (to the process variable value at the instant of resetting) or time elapsed value (to zero):

1. Se lect the dis play of the maxi mum value, mini mum value or time

elapsed value (as ap pro pri ate - see above).

2. De press the Raise key or Lower key for three sec onds.

The resetting of the value is indicated by the four-digit display showing:

for two sec onds be fore re vert ing to the maxi mum value or mini mum value dis play.

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Prod uct Man ual - Vol ume I Op era tor Mode

2.5 OVER-RANGE/UNDER-RANGE DISPLAYS

If the process variable attains a value higher than the input scale maximum limit (over-range) or lower than the input scale minimum limit (under-range), the upper display will show:

for the over-range condition and:

for the under-range condition.

2.6 SENSOR BREAK INDICATION

If a break is detected in the sensor circuit, the four-digit display will show:

The reaction of the alarms to a detected sensor break is dependent upon the input type.

2.7 COLD JUNCTION COMPENSATION DISABLED

If a thermocouple input is fitted, the Cold Junction Compensation should be enabled. If it is disabled, whenever the process variable is displayed, the unit display will be as shown on the right.

2.8 RESETTING THE LATCHED ALARM

If Output 1 is configured to be a latched alarm output, once it becomes active it will remain active (even if the alarm condition itself is cleared) until reset either from the front panel or via the Remote Reset hardware option. To reset the latched alarm from the front panel:

1. En sure that the nor mal Op er at ing Mode dis play (i.e. pro cess vari able)

is shown.

2. Press ei ther the Raise key or the Lower key for at least three sec onds.

The four-digit display will then show:

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for two seconds, indicating that the latched alarm has been reset. The latched Alarm 1 can be reset only if the original alarm condition has been cleared; this reset has no effect whilst the alarm condition prevails.

2.9 VIEWING THE HARDWARE DEFINITION CODE

The operator may view the current Hardware Definition Code setting in the four-digit display by simultaneously depressing the Lower and Scroll keys. A return may be made to the normal Operator Mode display by simultaneously depressing the Lower and Scroll keys.

NOTE: An automatic return is made to the normal Operator Mode display after 30 seconds.

To view the Hardware Option setting, press the Scroll key whilst the Hardware Definition Code is displayed. To return to the Hardware Definition Code display, depress the Lower and Scroll keys simultaneously.

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Prod uct Man ual - Vol ume I Set Up Mode

SEC TION 3

SET UP MODE

3.1 ENTRY INTO SET UP MODE

To enter Set Up Mode, with the instrument initially in Operator Mode displaying the process variable value, depress the Raise and Scroll keys simultaneously for three seconds. The instrument will then enter Set Up Mode and the SET indicator will come ON, the instrument still displaying the process variable value.

NOTE: If the four-digit display shows:

(i.e. all decimal point positions illuminated), this indicates that one or more of the critical Configuration Mode parameters - typically input range - have been altered in value/setting and, as a consequence, all Set Up Mode parameters have been automatically set to their default values/settings. To clear this display, simply alter the value/setting of any Set Up Mode parameter (see below).

The pa rame ters avail able for view/ad just ment in Set Up Mode are sum ma rised in Ta ble 3-1. When Set Up Mode is ac tive, the units dis play (nor mally oF, oC or blank) will show the single- character leg end for the se lected pa rame ter and the value for that pa rame ter will be shown in the four- digit dis play. The user may step through the Set Up Mode pa rame ters by de press ing the Scroll key. The value/set ting may be al tered us ing the Raise/Lower keys.

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Set Up Mode Prod uct Man ual - Vol ume I

Table 3-1 Set Up Pa rame ters

Parameter

Alarm 1 Value

Alarm 1 Hysteresis

Alarm 2 Value

Alarm 2 Hysteresis

Alarm 3 Value

Alarm 3 Hysteresis

Process Variable Offset

Digital Filter Time Const.

Legend

Adjustment Range

Range Min. to Range Max.

1 LSD to 10% of span expressed as display units

Range Min. to Range Max.

1 LSD to 10% of span expressed as display units

Range Min. to Range Max.

1 LSD to 10% of span expressed as display units

input span of instrument

0.0 secs. (OFF) to 100.0 secs. in

0.5 sec. increments.

Default

Range Max. (Proc. High) Range Min. (Proc. Low)

1 LSD

Range Max. (Proc. High) Range Min. (Proc. Low)

1 LSD

Range Max. (Proc. High) Range Min. (Proc. Low)

1 LSD

2.0 secs.

Linear Input Decimal Point Position

Linear Input Scale Range Minimum

Linear Input Scale Range Maximum

Recorder Output Scale Minimum

Recorder Output Scale Maximum

Operator Mode Display Strategy

0 (XXXX), 1 (XXX.X), 2 (XX.XX) or 3 (X.XXX)

–1999 to 9999

0, 1, 2, 3 or 4

0000

1000

Range Min.

Range Max.

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1. The legend for this parameter will be if only Alarm 1 is fitted/configured or if o ther alarms are fitted/configured.

2. These parameters appear in the display sequence only if Alarm 2 is fitted/configured.

3. These parameters appear in the display sequence only if Alarm 3 is fitted/configured.

4. Only applicable if a DC Linear input is fitted.

5. Defines the parameters displayed in sequence in Operator Mode:

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Prod uct Man ual - Vol ume I Set Up Mode

NOTES ON TABLE 3-1

Parameter Setting

PV value Max. PV value Min. PV value Elapsed Time

PV value Max. PV value Min. PV value

PV value

Alarm 1 value Alarm 2 value * Alarm 3 value *

* If configured/fitted

PV value Max. PV value Min. PV value

Alarm 1 value Alarm 2 value * Alarm 3 value *

PV value Max. PV value Min. PV value Elapsed Time Alarm 1 value

Alarm 2 value *

Alarm 3 value

3.2 ALAR M 1 VALUE or

If Alarm 1 is selected to be a Process High alarm, this defines the process variable value at or above which Alarm 1 will be active; the default value will be Input Range Maximum. If Alarm 1 is selected to be a Process Low alarm, this defines the process variable value at or below which Alarm 1 will be active; the default value will be Input Range Minimum. Its value may be adjusted between Input Range Maximum and Input Range Minimum. Alarm operation is illustrated in Figure 3-1.

3.3 ALARM 1 HYSTERESIS

This parameter applies a hysteresis band on the “safe” side of the Alarm 1 value. The effect of the hysteresis value on alarm operation is shown in Figure 3-2.

3.4 ALARM 2 VALUE

If Alarm 2 is selected to be a Process High alarm, this defines the process variable value at or above which Alarm 2 will be active; the default value will be Input Range Maximum. If Alarm 2 is selected to be a Process Low alarm, this defines the process variable value at or below which Alarm 2 will be active; the default value will be Input Range Minimum. Its value may be adjusted between Input Range Maximum and Input Range Minimum. Alarm operation is illustrated in Figure 3-1.

3.5 ALARM 2 HYSTERESIS

This parameter applies a hysteresis band on the “safe” side of the Alarm 2 value. The effect of the hysteresis value on alarm operation is shown in Figure 3-2.

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3.6 ALARM 3 VALUE

If Alarm 3 is selected to be a Process High alarm, this defines the process variable value at or above which Alarm 3 will be active; the default value will be Input Range Maximum. If Alarm 3 is selected to be a Process Low alarm, this defines the process variable value at or below which Alarm 3 will be active; the default value will be Input Range Minimum. Its value may be adjusted between Input Range Maximum and Input Range Minimum. Alarm operation is illustrated in Figure 3-1.

3.7 ALARM 3 HYSTERESIS

This parameter applies a hysteresis band on the “safe” side of the Alarm 3 value. The effect of the hysteresis value on alarm operation is shown in Figure 3-2.

3.8 PROCESS VARIABLE OFFSET

This parameter is used to modify the actual process variable value (measured at the input terminals) in the following manner:

Offset PV value = Actual PV value + Process Variable Offset value.

The offset process variable value is used for all PV-dependent functions (display, alarm, recorder output).

CAU TION: This is, in ef fect, a cali bra tion ad just ment. In ju di cious ap pli ca tion of val ues to this pa rame ter could lead to the dis played pro cess vari able value bear ing no mean ing ful re la tion ship to the ac tual pro cess vari able value.

There is no front panel in di ca tion when this pa rame ter is in ef fect (i.e. has been set to a non- zero value).

The default value is 0.

3.9 INPUT FILTER TIME CONSTANT

The input is equipped with a digital filter which is used to filter out any extraneous impulses on the process variable. This filtered PV is used for all PV-dependent functions (alarms etc.). The time constant for this filter may be adjusted in the range 0.0 seconds (filter OFF) to 100.0 seconds in 0.5 second increments. The default setting is

2.0 seconds. CAUTION: If this parameter is set excessively high, the indication

quality may be significantly impaired. The value chosen should be sufficiently large to attenuate stray noise but no larger.

3.10 LINEAR INPUT SCALE RANGE MINIMUM

This parameter, applicable only if a linear input is fitted, defines the scaled input value when the process variable input is at its minimum value. It is adjustable between –1999 and 9999 (with decimal point as defined by Linear Input Decimal Point Position). The default value is 0. This parameter can be set to a value greater than (but not equal to) Linear Input Scale Range Maximum, in which case the sense of the input is reversed.

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Prod uct Man ual - Vol ume I Set Up Mode

3.11 LINEAR INPUT SCALE RANGE MAXIMUM

This parameter, applicable only if a linear input is fitted, defines the scaled input value when the process variable input is at its maximum value. It is adjustable between –1999 and 9999 (with decimal point as defined by Linear Input Decimal Point Position). The default value is 1000. This parameter can be set to a value less than (but not equal to) Linear Input Scale Range Minimum, in which case the sense of the input is reversed.

3.12 RECORDER OUTPUT SCALE MINIMUM

This parameter defines the value of the process variable at which the Recorder Output reaches its minimum value; for example, for a 0 - 5V Recorder Output, this value corresponds to 0V. It may be adjusted within the range –1999 to 9999. The decimal point position for the Recorder Output is always the same as that for the process variable input range. The default value is Input Range Minimum. This parameter is not applicable if the Recorder Output option is not fitted.

NOTE: If this parameter is set to a value greater than that for the Recorder Output Scale Maximum (see Subsection 3.13), the relationship between the process variable value and the Recorder Output is reversed.

3.13 RECORDER OUTPUT SCALE MAXIMUM

This parameter defines the value of process variable at which the Recorder Output reaches its maximum value; for example, for a 0 - 5V Recorder Output, this value corresponds to 5V. It may be adjusted within the range –1999 to 9999. The decimal point position for the Recorder Output is always the same as that for the process variable input range. The default value is Input Range Maximum. This parameter is not applicable if the Recorder Output option is not fitted.

NOTE: If this parameter is set to a value less than that for the Recorder Output Scale Minimum (see Subsection 3.12), the relationship between the process variable/setpoint value and the Recorder Output is reversed.

3.14 OPERATOR MODE DISPLAY STRATEGY

This defines the sequence of parameter displays available in Operator Mode (see

NOTES ON TABLE 3-1).

3.15 EXIT FROM SET UP MODE

To leave Set Up Mode, select the initial Operator Mode display (process variable value) then depress the Raise and Scroll keys simultaneously, whereupon the SET indicator will go OFF and the instrument will return to Operator Mode.

NOTE: An automatic return to Operator mode will be executed if there is no key activity in Set Up Mode for one minute.

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Process High Alarm

direct-acting

Process High Alarm

reverse-acting

Process Low Alarm

direct-acting

Process Low Alarm

reverse-acting

PROCESS

HIGH

ALARM

PROCESS

LOW

ALARM

Figure 3-1 Alarm Op era tion

Alarm Hysteresis

Alarm Inactive

Process Variable

Alarm Hysteresis

Alarm Inactive

Alarm Active

Figure 3-2 Alarm Hys tere sis Op era tion

Alarm Value

Process Variable

Alarm Inactive

Alarm Value

Alarm InactiveAlarm Active

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Product Man ual - Vol ume I RS485 Se rial Com mu ni ca tions

SEC TION 4

RS485 SERIAL COMMUNICATIONS

This three-wire RS485-compatible serial communications option is the means by which communication may occur between the instrument and a master device (e.g. a computer or terminal).

4.1 PHYSICAL REQUIREMENTS

There are two communications protocols available with this option:

(a) AS CII

(b) MOD BUS

4.1.1 Char ac ter Trans mis sion

Data format is fixed to be seven data bits and one stop bit. The Baud rate may be selected to be 1200, 2400, 4800 (default) or 9600 Baud. For ASCII protocol, the parity is even. For MODBUS protocol, the parity is selectable to be even, odd or none.

4.1.2 Line Turn- Round

AS CII Pro to col: The com mu ni ca tions link is op er ated as a multi- drop half

du plex sys tem. When a de vice is trans mit ting, it drives the trans mis sion lines to the ap pro pri ate lev els; when it is not trans mit ting, its out puts are set to a high im ped ance in or der that an other de vice can trans mit. It is im por tant that a trans mit ter re leases the trans mis sion lines be fore an other de vice starts trans mis sion. This im poses the fol low ing re straints on the mas ter de vice:

(a) The transmitter must release the transmission lines within 6ms of the end of the last character of a message being transmitted. Note that delays due to buffers such as those used in universal asynchronous receivers/transmitters (UARTs) within the master device must be taken into account.

(b) The transmitter must not start transmission until 6ms has elapsed since the reception of the last character of a message.

All in stru ments in this range hav ing an RS485 com mu ni ca tions fa cil ity ad here to this stan dard; thus, pro vided that the mas ter de vice con forms simi larly to the stan dard, there should be no line con ten tion prob lems.

MOD BUS Pro to col: The line turn- round tim ings ad here to the in dus try stan dard.

4.2 ASCII PROTOCOL

This protocol assumes half duplex communications. All communication is initiated by the master device. The master sends a command or query to the addressed slave and the slave replies with an acknowledgement of the command or the reply to the query. All messages, in either direction, comprise:

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(a) A Start of Message character (b) One or two address characters (uniquely defining the slave) (c) A parameter/data character string (d) An End of Message character

Messages from the master device may be one of four types:

Type 1: L {N} ? ? * Type 2: L {N} {P} {C} * Type 3: L {N} {P} # {DATA} * Type 4: L {N} {P} I *

where all characters are in ASCII code and:

L is the Start of Mes sage char ac ter (Hex 4C) {N} is the slave ad dress (in the range 1 - 32); ad dresses 1 - 9

may be rep re sented by a sin gle digit (e.g. 7) or in two- digit form, the first digit be ing zero (e.g. 07).

{P} is a char ac ter which iden ti fies the pa rame ter to be in ter ro -

gated/modi fied - see Ta ble 4-2. {C} is the com mand (see be low) # in di cates that {DATA} is to fol low (Hex 23) {DATA} is a string of nu meri cal data in AS CII code (see Ta ble 4-1) * is the End of Mes sage char ac ter (Hex 2A)

No space char ac ters are per mit ted in mes sages. Any syn tax er rors in a re ceived mes sage will cause the slave to is sue no re ply and await the Start of Mes sage char ac ter.

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Product Man ual - Vol ume I RS485 Se rial Com mu ni ca tions

Table 4-1 {DATA} Ele ment - Sign and Deci mal Point Po si tion

Identifier

Character

A B C D E F G

J L

N O Q

T Z

[ \ ]

{DATA} Content

abcd0 abcd1 abcd2 abcd3 abcd5 abcd6 abcd7 abcd8

Sign/Decimal Point Position

+abcd

+abc.d

+ab.cd

+a.bcd

–abcd

–abc.d

–ab.cd

–a.bcd

Table 4-2 Com mands/Pa rame ters and Iden ti fi ers

Parameter/Command

Maximum Process Variable value Minimum Process Variable value Alarm 1 value Alarm 1 Hysteresis value Alarm 2 value Alarm 2 Hysteresis value

Scale Range Maximum

Read Only Read Only Read/Write Read/Write Read/Write Read/Write Read/Write (linear inputs

only) - otherwise Read Only

Scale Range Minimum

Read/Write (linear inputs

only) - otherwise Read Only Process Variable Offset value Instrument Status

Process Variable value Alarm 3 value Alarm 3 Hysteresis

Scale Range Decimal Point Position

Read/Write

Read Only

Read/Write

Read/Write (linear inputs

only) - otherwise Read Only Time Elapsed Instrument Commands

Recorder Output Scale Maximum Recorder Output Scale Minimum Scan Table

Input Filter Time Constant value

Read Only

Write Only

Read/Write

Read Only

Read/Write

Operation

NOTES

1. Applicable only if Alarm 2 is configured.

2. See Subsection 4.3.15.

3. Applicable only if Alarm 3 is configured.

4. See Subsection 4.3.16.

5. Applicable only if Output 2 is configured as a Recorder Output.

6. See Subsection 4.3.17.

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4.2.1 Type 1 Mes sage

L {N} ? ? *

This message is used by the master device to determine whether the addressed slave is active. The reply from the slave instrument, if it is active, is

L {N} ? A *

An inactive instrument will give no reply.

4.2.2 Type 2 Mes sage

L {N} {P} {C} *

This type of message is used by the master device to interrogate or modify a parameter in the addressed instrument. {P} identifies the parameter (as defined in Table 4-2) and {C} represents the command to be executed, which may be one of the following:

+ (Hex 2B) - In cre ment the value of the pa rame ter de fined by {P} – (Hex 2D) - Dec re ment the value of the pa rame ter de fined by {P} ? (Hex 3F) - De ter mine the cur rent value of the pa rame ter de fined by {P}

The reply from the addressed instrument is of the form:

L {N} {P} {DATA} A *

where {DATA} comprises five ASCII-coded digits whose format is shown in Table 4-1. The data is the value requested in a query message or the new value of the parameter after modification. If the action requested by the message from the master device would result in an invalid value for that parameter (either because the requested new value would be outside the permitted range for that parameter or because the parameter is not modifiable), the instrument replies with a negative acknowledgement:

L {N} {P} {DATA} N *

The {DATA} string in the negative acknowledgement reply will be indeterminate.

Scan Tables

A parameter identifier character “]” in the message from the master device indicates that a “Scan Table” operation is required. This provides a facility for interrogating the values of a group of parameters and status in a single message from the master device. The reply to such a command would be in the form:

L {N} ] 25 aaaaa bbbbb ccccc ddddd eeeee A *

The digits aaaaa, bbbbb etc. are expressed as shown in Table 4-1. For further information, refer to Subsection 4.3.17.

4.2.3 Type 3 Mes sage

L {N} {P} # {DATA} *

This message type is used by the master device to set a parameter to the value specified in {DATA}. The command is not implemented immediately by the slave instrument; the slave will receive this command and will then wait for a Type 4 message (see below). Upon receipt of a Type 3 message, if the {DATA} content and the specified parameter are valid, the slave reply is of the form:

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