SentrySafe SPD 5.5.5 User Manual

TM

Sample Sequencer

Installation, Operation and

Maintenance Manual

SPD 5.5.5

Rev. 9

2/00

Web: www.sentry-equip.com

e-mail: [e-mail]

Sample Sequencer

Table of Contents

TABLE OF CONTENTS

Page

GENERAL SPECIFICATIONS ..........................................................................................5

Specification for Valve Output Board..................................................................6

Specification for Signal Switching Output Board ................................................6

Specification for 0-1 Volt DC Output Board ........................................................7

Specification for Remote Electronic Track & Hold Board ...................................7

Specification for Plug-In Track & Hold Board .....................................................8

SAFETY PRECAUTIONS................................................................................................10

GENERAL DESCRIPTION..............................................................................................11

Modes of Operation ..........................................................................................11

Output Boards and CRT Display ......................................................................15

Optional Manifolded Sampling Valve................................................................16

OPERATION ...................................................................................................................17

Description of Controls .....................................................................................17

I/O Board DIP Switches ....................................................................................19

Membrane Switch Keys ....................................................................................21

Programming ....................................................................................................21

Display Functions .............................................................................................23

Operating Modes ..............................................................................................25

Off ................................................................................................................25

Cycle............................................................................................................25

Batch............................................................................................................28

Turning Sample Streams On & Off ...................................................................29

Advancing Streams...........................................................................................30

Holding on One Sample Point ..........................................................................30

Alarms...............................................................................................................30

Sample Nametag .............................................................................................. 32

INSTALLATION...............................................................................................................33

Unpacking.........................................................................................................33

Mounting ...........................................................................................................33

Power and Ground Connection ........................................................................37

I/O board Connections and Settings.................................................................38

Sample Valve Electrical Connection to Valve Output Board ............................38

Sample Valve Piping........................................................................................ 40

Recorder Signal Connections ...........................................................................40

Signal Switching Output Board (P/N 6-02499C)...............................................42

O-1 Volt Signal Switching Output Board...........................................................44

Remote Electronic Track & Hold Boards (P/N 7-00839A) ............................... 46

Plug-In Track & Hold Board (P/N 6-02499E) ....................................................47

Alarm Signal Connections ................................................................................48

Starting Up the Sample Sequencer ..................................................................49

MAINTENANCE ..............................................................................................................50

Fuses ................................................................................................................50

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

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1

Sample Sequencer

Table of Contents

TABLE OF CONTENTS

Page

Calibration.........................................................................................................50

Analog Output Calibration of the Remote Electronic Track & Hold

Board (7-00839A) .............................................................................................51

Analog Output Calibration of the Plug-in Electronic Track & Hold Board

(P/N 6-02499E).................................................................................................51

TROUBLESHOOTING ....................................................................................................53

COMPUTER COMMUNICATIONS .................................................................................55

SEQUENCE Monitor Program..........................................................................55

Communication Protocol...................................................................................56

SERVICE.........................................................................................................................57

SPARE PARTS LIST.......................................................................................................58

ACCESSORIES...............................................................................................................59

WARRANTY....................................................................................................................60

APPENDIX A: Configuring Sample Sequencer to Output 6 Volt DC on Alarm

Contacts of Signal Switching Output Board......................................................63

APPENDIX B: Recommended Piping for Sample Sequencer.......................................64

APPENDIX C: Procedure to Configure Remote Electronic Track & Hold

Board for 220/240 VAC Operation....................................................................65

APPENDIX D: Instructions to Operate a Hach Series 5000 Analyzer with a

Sample Sequencer ...........................................................................................66

APPENDIX E: Sample Sequencer Basic Electrical Wiring Diagram ..............................73

APPENDIX F: Plug-In Track & Hold Dual Point Configuration .......................................74

APPENDIX G: Retrofitting a Plug-In (Internal) Track & Hold Board in the Field ............77

APPENDIX H: Procedure to Configure Remote Track & Hold Card for

Voltage Input...........................................................................................79

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

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Sample Sequencer

Table of Contents

List of Figures

Page
Figure 1: Sample Sequencer System with Manifolded Sample Valve,

Recorder, Alarm Annunciator and Network

Computer Communications ........................................................................12

Figure 2: Sample Sequencer with Remote Electronic Track & Hold Board,
Manifolded Sample Valve, Recorder, Alarm Annunciator and

Network Computer Communications ..........................................................12

Figure 3: Batch Mode Sample Sequencer System with Manifolded Sample Valve,

Recorder, Alarm Annunciator and Network Computer Communications....13

Figure 4: Sample Sequencer System For Sensor Switching .....................................13

Figure 5: Sample Sequencer with Plug-In Electronic Track & Hold Board,

Manifolded Sample .....................................................................................14

Figure 6: Sample Sequencer Membrane Switch........................................................18

Figure 7: I/O Board Arrangement............................................................................... 20

Figure 8: Cycle Mode Timing Diagram.......................................................................27

Figure 9: Batch Mode Timing Diagram (for Batch-Type Analyzers)...........................28

Figure 10: Sample Nametag ........................................................................................32

Figure 11: Panel Mounting & Overall Dimensions, Sample Sequencer.......................34

Figure 12: NEMA 4X Rear Cover & Surface Mounting, Sample Sequencer................35

Figure 13: Enclosure Overall Dimensions, Remote Track & Hold ..............................35

Figure 14: Remote Valve Board Enclosure.................................................................. 36

Figure 15: I/O Board Connections ...............................................................................37

Figure 16: Solenoid Sample Valve Connections.......................................................... 39

Figure 17: Sample Sequencer Assembly (Rear View).................................................40

Figure 18: Sample Sequencer Assembly with Plug-In Track & Hold ...........................41

Figure 19: Recorder Connections: Signal Switching Using Signal Switching

Output Board ..............................................................................................42

Figure 20: Recorder Connections: Contact Closure Channel Indication Using

Signal Switching Output Board ...................................................................43

Figure 21: Recorder Connections for One or More Analyzers Using 0-1 VDC

Output Relay Board ....................................................................................44

Figure 22: Recorder Connections Using Remote Track & Hold Output Board(s) &

Signal Switching Output Board ...................................................................46

Figure 23: Recorder Connections Using Plug-In Track & Hold Output Board(s) .........47

Figure 24: Alarm Connections .....................................................................................48

Figure B1: Recommended Sample Conditioning for Switching Streams to an

Analyzer......................................................................................................64

Figure C1: Remote Electronic Output Board Arrangement ..........................................65

Figure D1: Wiring to Hach Series 5000 Analyzer, Models 60000 - 60004 ...................69

Figure D2: Recommended Sample Conditioning for

Switching Streams to a Hach 5000 Analyzer ............................................ 70

Figure D3: Electrical Transmittal Sample Sequencer & Manifold valves......................71

Figure D4: Valve Transmittal Sample Sequencer & Manifold Valves...........................72

Figure E1: Sample Sequencer Basic Electrical Wiring Diagram ..................................73

Figure F1: Component View......................................................................................... 74

Figure F2: Wiring Diagram - Dual Outputs from Plug-In Track Hold Board .................76

Figure H1: Remote T/H Board, Configuration for Voltage Input ...................................79

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

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3

Sample Sequencer

Page

Table 1: Control and Display Descriptions................................................................17

Table 2: I/O Board DIP Switch (SW1) Functions ......................................................19

Sample Sequencer models which have internal track and hold have passed

applicable tests for the European Community 89/336EEC EMC Directive. The
product is marked and shipped with a Declaration of Conformity. Contact Sentry
Equipment with further questions.

Table of Contents

List of Tables

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

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4

Sample Sequencer

GENERAL SPECIFICATIONS*

Applications: The Sample Sequencer is designed to support sample stream switching in the batch or

cycle modes. The Sample Sequencer can also switch sensor signals.

Design: Microprocessor-based with non-volatile memory and RS-485 communications

Maximum Number of Samples: 8

Power: 108-132/216-264 Vac, 47-63 Hz, Usage = 3.8VA without Plug-In Track & Hold (Uses external

UL/CSA or TUV-approved 6 VDC power supply.) Maximum 14VA with Plug-In Track & Hold.

Inputs from Analyzer:

• One analog input: 0-20 mA or 4-20 mA

• One digital input (dry contact closure) for indications of end-of-analysis signal for batch
mode operation

• One digital input (dry contact closure) for analyzer system alarm indication. This signal
shuts off Sample Sequencer and valves.

Outputs:

Standard Outputs:

• RS-485 serial communication port (for networking any RS-485 units to a PC)

• Valve Output Board to control maximum eight solenoid valves (DC or maximum 250 Vac
solenoids) for sample stream switching

• Plug-in Signal Switching Output Board with eight DPDT relays for analog signal switching
or contact closure for point number indication. The second pole of each point relay is used
for low voltage commutated analog alarm and analyzer system alarm indication for each
point.

Optional Input & Output Boards:

• Plug-in 0-1VDC Output Board with eight DPDT relays for 0-1 VDC output of sample point
number. The second pole of each point relay is used for low voltage commutated analog
alarm and analyzer system alarm indication for each point.

• Remote Electronic Track & Hold Board to output and hold analog signals (track & hold) of
four points. Two analog output boards may be used to provide eight total channels of
analog output. Use the remote electronic track & hold boards in combination with one
Plug-in Signal Switching Output Board.

• Remote Cell Switching Board to switch maximum eight cells

• Plug-In Track & Hold Board to output and hold four analog signals per circuit board. A
maximum of two plug-in Track & Hold boards may be installed in Sample Sequencer
enclosure. Use of two Plug-In Track & Hold boards requires that the valve circuit board be
mounted remote from Sample Sequencer.

Note: If you are retrofitting a Plug-In Track & Hold to an existing Sequencer in the field,

see Appendix G.

Accuracy of Sequencer: +/- 0.1% full scale, standard unit

+/- 0.2% full scale, with Internal Track & Hold Boards
User Interfaces: Integral membrane switch keypad and IBM compatible PC with serial port
* Sentry reserves the right to revise specifications at any time.

Specifications

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

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Sample Sequencer

Display: Red alphanumeric LED read-out display of channel number, time, alarms, analog signal and

station number. Eight red LEDs for point number indication and alarm annunciation.
Removable sample name tag.

Case: Material: Noryl; NEMA-4X on face-plate with NEMA 12 rear cover. Option: NEMA 4X

backplate for surface mounting. 5.35" x 5.35" x 6.26" deep.

Mounting: Panel or surface mount.

Ambient Temperature: 0-60C; RH 90% max. non-condensing at 40 C max.

Shipping Weight: 5 lbs (2.3 Kg)

Specification for Valve Output Board

Purpose: The valve output board controls contacts which supply power to solenoid valves.

Inputs: Logic-level signals from Sample Sequencer

Number
of Points: 8

Relays: DPDT sealed relays, contacts rated for 250 VAC, 220VDC maximum operating voltage.

Maximum switching capacity 30W, 62.5 VA for inductive loads.
Point number
indication: Nine red LEDs on circuit board with point number silkscreened on board. One LED is for Off

status and eight LEDs are for point number indication.

Enclosure (optional for remote mounting): NEMA 4X , IEC 529, IP 67 with knockouts.

Specification for Signal Switching Output Board

Purpose: The output relay board is used to switch analyzer 0-20 mA or 4-20 mA signals provide dry

contact sample point number indication. The board includes alarm contacts for normally-open

commutated alarm indication.
Inputs: 0-20 mA or 4-20 mA signal from analyzer (if signal switching)
Number
of Points: 8
Relays: DPDT sealed relays, contacts rated for 250 VAC, 220VDC maximum operating voltage.

Maximum switching capacity 30W, 62.5 VA for inductive loads. The alarm contacts are

normally-open dry contacts which may be powered by field voltage (less than 30 VDC and 0.5

A) from annunciator. In lieu of this standard alarm set-up, the board can be reconfigured to

supply 6 VDC to remote devices, i.e., relay coils, to accommodate required high voltage alarm

requirements. (See Appendix A.)

Specifications

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

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Sample Sequencer

Specification for 0-1 Volt DC Output Board

Purpose: The 0-1 VDC output board is used to provide 0-1 VDC sample point number indication. The

board includes alarm contacts for normally-open commutated alarm indication.

Inputs: None

Outputs: One 0-1 Volt DC signal to indicate respective sample point number currently in "dwell" time.

Number
of Points: 8

Relays: DPDT sealed relays, contacts rated for 250 VAC, 220VDC maximum operating voltage.

Maximum switching capacity 30W, 62.5 VA for inductive loads. The alarm contacts are
normally-open dry contacts which may be powered by field voltage (less than 30 VDC and 0.5
A) from annunciator. In lieu of this standard alarm set-up, the board can be reconfigured to
supply 6 VDC to remote devices, i.e., relay coils, to accommodate required high voltage
alarm requirements. (See Appendix A)

Specification for Remote Electronic Track & Hold Board Assembly (7-00839A)

Purpose: The remote track & hold card has four independently isolated channels which each operate in

two modes: the track mode, where the output follows proportionally to the input while contact
terminals are closed, and the hold mode, where the output value is held via digital memory
until the command is reset by contact closure.

This card is ideal for applications with analyzers being sequenced between multiple sample

lines. The hold feature permits the last reading for each of four channels to be held until the
next sequenced reading for the respective channel occurs. Use of the card prevents the non­active channels from dropping to zero between readings thereby avoiding potential system
alarm problems.

The remote Track & Hold board is mounted in an enclosure remotely located from the Sample

Sequencer enclosure. The advantage of using the remote Track & Hold instead of the plug-in
type is that alarm contacts are available from the signal switching board. Another advantage
of the remote track and hold is that it can be configured to provide multiple isolated outputs.

If a sample point is not activated after four contact closure indications have occurred on the

board, the output of the unactivated point will become 4 mA. If no sample points on the board
are activated within 80 minutes, all four outputs will become 4 mA.

The card is versatile to accommodate many applications. Several cards may be wired

together to provide more than four channel outputs. The card is also useful for applications
where multiple outputs from one analog input signal are required. For instance, the card may
be used if separate analog signals for plant DCS and recorders are required.

Performance:
Accuracy ± .01% of span at 25°C
Response Time: One-second time constant
Temperature coefficient: ± 0.012% reading per 1°C

Specifications

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

Web: www.sentry-equip.com • e-mail: [e-mail]

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Sample Sequencer

Input Analog Signal: 0-20 mA or 4-20 mA or any voltage input between 0-10 V with proper

scaling resistor (plug-in socket scaling resistor - See Appendix H).
Output Analog Signals: Four 0-20 mA or 4-20 mA independently isolated at minimum 500 V
per channel
Maximum Load Resistance: 600 Ohms

Enclosure: NEMA 4X, IEC529, IP67 with knockouts.

General: Power: 108-132/216-264 Vac, 47-63 Hz (jumpers for 220 Vac applications - See Appendix F)
Wiring: Screw Terminals
Enclosure: ABS watertight NEMA 1,2,3,3R,4,4X, 5,12 & 13. Europe: IP 65 to DIN 40050
Enclosure Dimensions/Mounting: 9.44" x 6.29" x 3.54" / Wall or surface mounting
Adjustments: Offset and Gain potentiometers for each output channel
Hold Control: Holds when opening the input control terminals; tracks when closing the

control terminals (tracks one channel at a time)
Operating Temperature: -5 to +70°C
Operating Humidity: 90% RH max., non-condensing
Weight: 2.3 lbs.

Specification for Plug-In Electronic Track & Hold Board (6-02499E)

Purpose: The plug-in track & hold card has four independently isolated channels which each operate in

two modes: the track mode, where the output follows proportionally to the input during the

respective dwell time, and the hold mode, where the output value is held via digital memory

until the next dwell time.

This card is ideal for applications with analyzers being sequenced between multiple sample

lines. The hold feature permits the last reading for each of four channels to be held until the

next sequenced reading for the respective channel occurs. Use of the card prevents the non-

active channels from dropping to zero between readings thereby avoiding potential system

alarm problems.

The card is versatile to accommodate many applications. One or two circuit cards may be

plugged inside the Sample Sequencer to provide up to eight sample outputs.

The card can be used for applications where dual outputs from one analog input signal are

required. Dual outputs are obtained by field configuration. For instance, the card may be

used if dual analog signals for plant DCS and recorders are required. A maximum of four

outputs or two pairs, may be obtained from each card.

The plug-in track and hold board will output 0 mA on points which are turned off.

Input Analog Signal: 0-20 mA or 4-20 mA
Output Analog Signals: Four 0-20 mA or 4-20 mA independently isolated at minimum 500 V
per channel per circuit board.
Maximum Load Resistance: 525 Ohms

Specifications

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

Web: www.sentry-equip.com • e-mail: [e-mail]

8

Sample Sequencer

General: Wiring: Screw Terminals
Circuit Board Dimensions: 5.165" x 5.6"
Adjustments: Offset and Gain potentiometers for each output channel.
Operating Temperature: -5 to +70°C
Operating Humidity: 90% RH max., non-condensing
Weight: 5 oz.

Specifications

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

Web: www.sentry-equip.com • e-mail: [e-mail]

9

Sample Sequencer

Safety Precautions

SAFETY PRECAUTIONS

Before attempting to unpack, set up or operate this product, read the entire

manual. Pay careful attention to all warnings, cautions and notes. Failure

to do so could result in serious personal injury or equipment damage.

Product warranty may be affected.

Use of Hazard Information

If multiple hazards exist, the signal word corresponding to the greatest

hazard shall be used.

DANGER

Indicates an imminently hazardous situation which, if not avoided will result

in death or serious injury

WARNING

Indicates a potentially hazardous situation that could result in death or

serious injury

CAUTION

Indicates a potentially hazardous situation that may result in minor or

moderate injury

NOTE

Information that requires special emphasis.

SHALL

This word understood to be mandatory

SHOULD

This word understood to be advisory

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

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10

Sample Sequencer

General Description

General Description

The SENTRY Sample Sequencer is a microprocessor-based instrument capable of electronically
switching up to eight sample streams or sensors one at a time to one analyzer and of providing
signals to recorders, alarms and computers. A manifolded Sentry sampling valve specially designed
to obtain optimum representative samples is available for sample stream switching with the Sample
Sequencer. The Sample Sequencer reduces the number of required analyzers while maintaining
equivalent data accuracy. Reliable sample analysis comparison is obtained by using a Sample
Sequencer with one dedicated analyzer. In addition, significant operation cost savings are obtained
by not having to install, maintain and service multiple analyzers.

The Sample Sequencer is capable of operating in the cycle mode for continuous-type analyzers or in
the batch mode for batch-type analyzers. In addition, the Sequencer is capable of measuring the
analyzer analog output signal and converting the analog signal to digital data to be sent out via the
Sequencer's RS-485 serial data communication port. Using the RS-485 capability, one can connect a
PC via twisted pair cable to one or more sequencers for remote monitoring, control and data
acquisition.

Plug-in output boards are supplied to switch the analyzer analog signal to different recorder points or
to provide contact closure channel number indication for recorders. The boards also provide eight
independent commutated alarm contacts for low/high analog alarm and analyzer system alarm
indication. Optional boards are available to provide 0-1 VDC channel number indication for recorders
or to track and hold independently isolated analog signals.

Figures 1 - 3 illustrate a typical system arrangement for sample stream switching with the Sample
Sequencer. Optional boards and customer-supplied equipment are shown for clarification.

Figure 4 illustrates a typical system arrangement for sensor switching with the Sample Sequencer.
Optional boards and customer-supplied equipment are shown for clarification.

Modes of Operation
The Sample Sequencer has three programmable modes of operation:

BATCH - For analyzers that take a sample "bite" (or batch), produce an analytical result

and then provide a contact signal output, in typically one to 20 minutes.

CYCLE - For any continuous analysis (conductivity, dissolved oxygen, pH and sodium).

Note

If using the Sample Sequencer with a Hach analyzer, See Appendix D.

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

Web: www.sentry-equip.com • e-mail: [e-mail]

11

Sample Sequencer

General Description

FIGURE 1 - Sample Sequencer System with Manifolded Sample Valve, Recorder, Alarm Annunciator and

FIGURE 1 - Sample Sequencer System with Manifolded Sample Valve, Recorder, Alarm Annunciator and

Network Computer Communications

Network Computer Communications

FIGURE 2 - Sample Sequencer with Remote Electronic Track & Hold Board, FIGURE 2 - Sample Sequencer with Remote Electronic Track & Hold Board,

Manifolded Sample Valve, Recorder, Alarm Annunciator and Network Computer Communications Manifolded Sample Valve, Recorder, Alarm Annunciator and Network Computer Communications

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

Web: www.sentry-equip.com • e-mail: [e-mail]

12

Sample Sequencer

General Description

FIGURE 3 - Batch Mode Sample Sequencer System with Manifolded Sample Valve, Recorder, Alarm

Annunciator and Network Computer Communications

(See Appendix D for use with Hach analyzer.)

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

FIGURE 4 - Sample Sequencer System for Sensor Switching

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13

Sample Sequencer

General Description

Figure 5 - Sample Sequencer with Plug-In Electronic Track & Hold Board, Manifolded Sample

Valve, Recorder and Network Computer Communications

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

Web: www.sentry-equip.com • e-mail: [e-mail]

14

Sample Sequencer

General Description

Output Boards and CRT Display

Output boards are available for the Sample Sequencer to provide a variety of outputs.

Valve Output Board
DC) electrically operated valves for switching up to eight sample streams to one analyzer. The board
may be located inside the Sample Sequencer. As an option, the valve output board may be housed in
a NEMA 4X enclosure for remote installations. The board includes lights to indicate current sample
point number. For use with the Sample Sequencer, Sentry offers a special sampling valve for stream
switching. The unique design prevents cross contamination and maintains continuously flowing
samples to help provide a representative sample.

Signal Switching Output Board for Signal Switching or Contact Closure Point Indication
switching output board with double pole, double throw relays is available to commutate the analyzer
analog signal (signal switching) and low voltage normally-open alarm outputs to eight individual outputs.
This output works well with a multipoint recorder with print holdout option. The signal switching output
board may also be used with a recorder which requires a contact closure to indicate the current sample
point number.

0-1 VDC Signal Output Board (optional)
an analog signal of 0 - 1 Volt DC indicating the current sample point number. For example, sample
point number one is indicated by an output of 0.1 Volt, point two by 0.2 Volt, ..., and point eight by 0.8
Volt. This option works well when there are insufficient channels on the recorder for all of the analog
signals. For example, it can be used when a two channel recorder is available to sequence more than
two streams. In addition, it can be used if each sample stream goes through multiple analyzers. The
board also provides eight commutated low voltage normally-open alarm contacts.

Electronic Track & Hold Boards:
Plug-in Type
Sequencer and is used to track and hold a 0 - 20 or 4 - 20 milliamp signal as output for that point in up
to four separately isolated outputs. Two plug-in (6-02499E) electronic track & hold boards may be
plugged into the Sample Sequencer to obtain maximum eight points of track and hold output. The
electronic track & hold board has no alarms. Use the remote type electronic track & hold board (below)
with a signal switching output board if alarm contacts are required.

NOTE: Only one type
electronic track & hold boards), may be used in
Remote Type
in type. However, it requires line power and contact closure inputs to indicate tracking sample point
number. This board is used in conjunction with the signal switching output board. See specification for
more information.
CRT Monitor Output
controller computer to a remote computer, controller, or annunciator as all the information is available
and can be transmitted using RS-485. Additional Sample Sequencers may also be connected on the
RS-485 network. Sentry offers a computer program, SEQUENCE, to control, monitor, graph and
record data from a Sample Sequencer.

: The valve output board uses relays to turn on and off maximum 250 Volts (AC or

: The signal

: The 0 - 1 Volt DC signal output board is available to provide

: The plug-in electronic track & hold board installs inside the Sample

of signal output board, (i.e., signal switching, 0-1 VDC output, or two plug-in

a Sample Sequencer at a time.

: The remote electronic track & hold board (7-00839A) is similar to the plug-

: A simple computer program can be written to communicate from the

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

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15

Sample Sequencer

OPTIONAL MANIFOLDED SAMPLING VALVE

Although the Sample Sequencer may be used to control most manifolded valve arrangements, the
Sentry Manifolded Sample Valve offers a convenient optional accessory to obtain a representative
sample. The patented design incorporates block and bleed design and provides continuously flowing
samples with no areas for cross contamination to occur. The valve is available with a variety of DC and
AC solenoid coils and comes in either four or eight sample line models. Contact Sentry for more
information about this special sampling valve.

General Description

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

Web: www.sentry-equip.com • e-mail: [e-mail]

16

Sample Sequencer

Operation

OPERATION

Description of Controls

Figure 6 and Table 1 describe controls on the Sample Sequencer membrane switch display.

Table 1 - Control and Display Descriptions

DESCRIPTION FUNCTION

Sample Point switches 1-8 with
light annunciators

Sample names The removable name tag allows the sample name to be typed and

Sample point display Indicates the sample point number corresponding to the value in the

Display function display window Indicates the value of the current function (indicated by the display

Display function lights Indicates which function (CYCLE TIME, DELAY TIME, DWELL TIME,

Control switches These tactile feedback switches control the displays, reset alarms and

Programming switch & arrows Activates the programming mode to program new values for all display

Analyzer system alarm light When lit, indicates an analyzer system alarm.

Pushing the switches turns the sample point on and off. The adjacent
light turns on when the point is on. The light blinks on and off when the
point is in alarm. When the point is on, the respective sample (when
sample switching) or cell signal (when sensor switching) will be
analyzed in sequence.

displayed through the clear pocket on the membrane switch. The
nametag is accessed by removing the front display plate.

display function window.

function light which is on).

ANALOG mA, LOW ALARM, HIGH ALARM or STATION NUMBER) is
currently being displayed.

start or restart the Sample Sequencer. The DISPLAY, NEXT and
ALARM RESET keys serve a different purpose when programming
(see below).

functions except ANALOG mA. For example, new values for CYCLE
TIME or LOW ALARMS can be programmed. The arrows light up
when the programming mode is activated. The control switches
immediately above the arrows control the digit position and value when
programming. For example, the DISPLAY switch becomes the "up
arrow" function to increase the function display digit value when
programming.

SENTRY Equipment Corp • P. O. Box 127 • Oconomowoc, WI 53066 • 262/567-7256 • FAX: [phone]

Web: www.sentry-equip.com • e-mail: [e-mail]

17

Sample Sequencer

Operation

FIGURE 6 - Sample Sequencer Membrane Switch

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18

Sample Sequencer

Operation

I/O Board DIP Switches

Figure 7 shows the location of the four DIP switches at SW1 on the I/O board. The I/O board is
normally supplied in the Sample Sequencer and plugs into the display board with the long dual-row 42
pin connector. The SW1 DIP switch functions are described in Table 2 below.

Table 2 I/O Board DIP Switch (SW1) Functions

SW1
No.

1

2

3

4

SW1-1
position. The ON position enables programming form the front panel.

SW1-2
installed. The switch should be in the off position if the Plug-in electronic track & hold board(s) is
used. Select the ON position if either the Signal switching, 0-1 Volt DC output or remote
hold board are used.

SW1-3
must be calibrated. This forces the Sequencer into a fixed state to conveniently calibrate the
Sample Sequencer via the gain and offset potentiometers on the display board. (See the
Calibration section in this manual for more information.) Turning the switch OFF turns off the
calibration mode and permits normal operation. The START/RESET control switch on the front
display must be pushed to start sequencing after completing calibration and turning SW1-3 OFF.
Note: The Sample Sequencer is shipped factory-calibrated.

SW1-4
enables the cycle mode for continuous type analyzers. The ON position enables the batch mode
for batch type analyzers, such as Hach Series 5000.

Description

Programming

Type of plug-in output board

Calibration

Operation Mode

allows one to lock-out front panel programming by putting this switch in the lock-out (OFF)

configures the Sample Sequencer for the type of plug-in output board which has been

enables the calibration mode. Turn the switch On when the ANALOG mA signal display

configures the Sample Sequencer for the desired mode of operation. The OFF position

Function

OFF ON

Lock-out

Plug-in electronic track &

hold board

Normal Operation

Cycle Mode

Signal switching output,

Enable

0-1 volt or Remote

track & hold boards

Calibrate Mode

Batch Mode

track &

See Appendix D if using the Sample Sequencer
with Hach Series 5000 analyzers.

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19

Sample Sequencer

Operation

FIGURE 7 - I/O Board Arrangement

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20

Sample Sequencer

Operation

Membrane Switch Keys

Sample Point Numbers (1-8): The eight sample point number switches turn a sample point on or off.
When the point is on, the adjacent LED will light and the sample point will be analyzed sequentially.

DISPLAY
the next one down and back to the top. Normally the CYCLE TIME function is selected to keep
track of the analyzer cycling, or ANALOG mA output is selected to keep track of the analyzer output
value. The remaining functions are used predominantly for set up, troubleshooting or programming.

NEXT
selections, one for each point. Pressing the NEXT key displays the next higher POINT value and
then back to one again.

ALARM RESET
Alarms can be from a low or high analog mA output value or from the analyzer system alarm. Eight
successive analyzer system alarms will force the Sample Sequencer to an "OFF" mode.

START/RESET
reinitializes and restarts with the first on point. The previous programmed values are read in from
non-volatile memory.

PROGRAM
out DIP switch on the I/O board (SW1-1 in Off position) can defeat this external key and lock-out
programming from the membrane switches.

Programming
In order to operate, the Sample Sequencer must be initially programmed. Programming is
accomplished either with the front display membrane switch keys or from computer signals via the
built-in RS-485 serial communications.

The following items are programmed to meet analyzer and operational requirements:

• Cycle time (or batch time-out when in the batch mode)

• Delay time

• Dwell time

• Low alarm levels for each point

• High alarm levels for each point

• Station number for communications

Except for station number, the above items can also be remotely programmed using the
communications software from a connected computer.

: Pressing this key causes the function as indicated by the function lights to advance to

: With functions: ANALOG mA output, LOW ALARMS, and HIGH ALARMS, there are eight

: Resets all current alarms. Points will realarm if the current value is still in alarm.

: If the key is pressed or the power is turned on, the Sample Sequencer resets,

: Pressing this key starts and stops programming as described below. An internal lock-

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21

Sample Sequencer

Operation

To Program:

• Press the DISPLAY key to select desired function. To select desired POINT number
for the low and high alarms press the NEXT key.

• Press PROGRAM. The programming arrows light up and the current programmed
value is displayed.

• Starting at the right digit, pressing the key immediately above the up arrow
(DISPLAY) causes the digit to increment. Press repeatedly until the desired digit is
displayed.

• Each pressing of the key above the left arrow (NEXT) shifts the active digit one to
the left. The active digit may be incremented using the aforementioned up arrow
key.

• Each pressing of the key above the right arrow key (ALARM RESET) shifts the active
digit one to the right.

• Pressing the PROGRAM key again:

 Turns the arrow lights off.
 Saves the value in permanent memory.
 Returns the Sample Sequencer to its normal display.
 The newly programmed values are active on the next cycle. Press

START/RESET to restart the sequencer using the new values.

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22

Sample Sequencer

Operation

Display Functions:

Functions shown in Figure 6 may be displayed on the Sample Sequencer. Pressing the DISPLAY key
toggles through the below functions. The light adjacent to the display function lights to indicate the function
is displayed. The NEXT key toggles through successive function point numbers (1-8) for ANALOG mA,
LOW ALARM and HIGH ALARM.

• CYCLE TIME (or time-out count-down for batch mode) - time duration to sample a point

• DELAY TIME - time to delay the analysis signal upon starting the cycle

• DWELL TIME - time period that analysis signal is read and switched after delay

• The following three items display milliamp values of 0 to 20 mA . Values for each of the
eight points are displayed by pressing the NEXT key.

 ANALOG mA - the input analysis signal value
 LOW ALARM values
 HIGH ALARM values

• STATION NUMBER used in communications (1-16).

CYCLE TIME, DELAY TIME and DWELL TIME are discussed in the operating mode section below.

ANALOG mA Input Analysis Value
milliampere range. On selection, the value for sample point number one is displayed. Pressing the NEXT
key will display the next higher point up to eight, and then from eight back to one. As the unit processes the
active sample points, any points not on will be skipped and the value zeroed. In cycle or batch mode
(described below) the values are retained only for the time required to complete an analysis circuit of the on
points. In manual mode only the active point is on. If the unit is in the OFF mode, all values are zeroed.

If an optional electronic track & hold board is used to provide individual milliampere outputs, all eight values
are refreshed each second. If a signal switching output board is used, the active value is output during the
dwell time only. All values are immediately available to a computer connected to the communication port.

LOW ALARM LEVEL:
Pressing the NEXT key displays successive values. To reprogram a low alarm value, press the
PROGRAM key and follow the directions in the section on programming. Pressing the PROGRAM key
again terminates programming and saves the value in non-volatile memory. These values are also
programmed by communicating the required protocol from a connected computer and current values can
be sent, on request, from the Sample Sequencer to a computer. Note: The low and high alarm values are
programmed in milliamp values. Selection of the appropriate value should take the analyzer's
measurement range and span into consideration.

During the valid dwell output time, depending on the mode, the input signal is compared to the low alarm
level and if the signal is less, an alarm state is initiated for that point. The respective sample point light on
the Sample Sequencer display at that point selection switch will blink each second. Pressing the alarm
reset key stops the blinking, but the alarm can reinitiate if the condition still exists and is dwelling on the
point number. If an optional signal switching output board is used, a low voltage (<30 VDC) dry contact
closure alarm signal or 6 VDC output signal is commutated, depending on board configuration.

HIGH ALARM LEVEL:
equal to the programmed high alarm value.

STATION NUMBER:
Sequencer unit. The station number identifies the unit when operated with the built-in RS-485 serial
communication network. This station number should be different from other Sample Sequencers on the
computer network. The station number assignment can only be performed with the front panel display

The programmable low alarm level in milliamps is displayed for each sample point.

Functions the same as for low alarms, but will go into alarm if the input signal is

The station number function assigns a station number of 1 to 16 to the Sample

: All analog values are in milliampere form for either 0 to 20 or 4 to 20

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23

Sample Sequencer

PROGRAM key on the Sample Sequencer. The programming procedure is similar to that described for
programming the alarms. See the manual section on communications for more information about the
network communications.

Operation

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24