Black Box 945 User Manual

How To Use

Data Communications

with the Watlow

Series 945

User's Manual

Watlow Controls, 1241 Bundy Blvd., P.O.Box 5580, Winona, MN 55987-5580, Phone: [phone], Fax: [phone]

W945-SA50-9210
March, 1992

Supersedes:
W945-SA40-9119

How to Use Data Communications

Made in the U.S.A.

$5.00

Printed on Recycled Paper

WATLOW Series 945

1

Contents

Page Item

3 Data Communications and the Series 945
3 Hardware Interfaces Protocols
3 Communications Wiring
4 RS-422A Interface Pinouts
5 RS-423A Interface Pinouts

(RS-232C Compatible)
6 EIA-485 Interface Pinouts
6 Connecting the Control and Computer
7 Setting Hardware Protocol Switches
7 Network Connections
7 Series 945 Communication Parameters
8 Communications Setup Parameters
10 ASCII and Series 945 Information
11 Series 945 General Message Syntax
11 Message Syntax
11 Data Rules
12 Command List
12 Example Format
13 XON/XOFF Protocol for RS-423A
13 Start and Stop Communicating with the

Series 945 and XON/XOFF
14 XON/XOFF "=" Command Example
15 XON/XOFF "?" Command Example
16 ANSI X3.28 Protocol for RS-422 & EIA-485
16 Device Address
16 Starting Communications in ANSI X3.28
17 Stopping Communications in ANSI X3.28
17 ANSI X3.28 "=" Command Example
18 ANSI X3.28 "?" Command Example
19 "?" Command
20 "=" Command
22 Data Logging
23 Table Printout
23 Statistical Process Control - SPC
24 The Difference Between Control and

Specification Limits
25 Chart and SPC Printout
26 NAKs and Error Codes
26 User Responsibility
27 Index

Figures Item

1 RS-422 Interface Wiring
2 RS-423 Interface Wiring
3 EIA-485 Interface Wiring
4 RS-422/RS-423 Switch Selection
5 General Message Syntax Example
6 XON/XOFF "=" Command Example
7 XON/XOFF "?" Command Example
8 ANSI X3.28 "=" Command Example
9 ANSI X3.28 "?" Command Example
10 Data Logging Interface Wiring
11 Table Printout Example
12 Chart & SPC Printout Example

Tables Item

1 Setup Menu Prompts and Descriptions
2 ASCII Character Set
3 ASCII Control Characters (Partial Set)
4 Address to ASCII Conversion
5 "?" Command Data and Responses,

Partial Set
6 "=" Command and "?" Command Data
7 Printer Troubleshooting

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WATLOW Series 945

How to Use Data Communications

How to Use Data Communications

with the Watlow Series 945

This manual is a supplement to the Series 945 User's Manual. It is for users with
the data communications option. Use in conjunction with the Series 945 User's
Manual.

This is expert user-level material and requires previous experience with data
communications.

Two Serial Hardware Interfaces and
Two Software Protocols

Depending on your units model number, you may have one of two hardware
interfaces:

1)RS-422A for a "multidrop" or (multiple device) network, up to ten devices total;
with 4000 ft. network length limit, or RS-423A (RS-232C compatible) for one on
one communication with a 50 ft. network length limit with a 945 and a host
computer (945A-XXXX--B000). Selecting RS-422A or RS-423A is user select­able via internal switches. See Page 7.

Data Comm

2)EIA-485 (945A-XXXX-D000) also for a multidrop network, up to 32
addresses total, and with a 4000 ft. network length limit.

There are two protocols available to you. Depending on the type of network you
need, you must use the correct combination of interface and protocol.

We use ANSI X3.28 Protocol, based on ANSI X3.28 - 1976 Subcategories 2.2,
and A3, with the RS-422A and EIA-485 interface to run a multiple device network.
We also use XON/XOFF Protocol, a simpler protocol, to run a two device network
with an RS-423A interface. XON/XOFF will also work with the RS-422A and EIA­485 interface, but the network is limited to two devices (one computer or printer
and a Series 945). XON/XOFF Protocol requires no responses to messages like
the ANSI X3.28 Protocol does. Likewise, ANSI X3.28 Protocol, which provides a
response to every message, will work with the RS-423 interface. But again you are
limited to one Series 945 and a host computer or printer.

To select which protocol you are going to use, go into the SETUP menu and use
the MODE key to advance to the Prot parameter. Select either FULL, for ANSI
X3.28 2.2 - A.3, or On for XON - XOFF.

If you are using ANSI X3.28 Protocol, choose an address number for the control
under the Addr parameter following the Prot parameter. This parameter will only
appear if Prot = FULL.

Communications Wiring

To connect your Series 945 to a computer or printer, use the next three pages as a
reference. Your computer or printer hardware manual will provide more detailed
serial port pin information. Also refer to the noise prevention section in Appendix 1
of the Series 945 User's Manual. In the often noisy environments of industrial
locations, it is important not to take noise isolation lightly.

How to Use Data Communications

WATLOW Series 945

3

1

0

RS-422A

Figure 1 ­RS-422A Interface,

Pin Designations.

Series 945 #

RS-422A Interface Pinouts

945A-XXXX-B000

The RS-422A communications uses a four wire (full duplex) system. There are
two separate lines for transmitting, and two lines for receiving data between the
computer and the Series 945. With RS-422A you can have from one to ten Series
945 controls connected to a single computer.

This diagram is a typical wiring example. The connections on the host computer
may vary depending on models. Refer to your computer user's manual for more
information.

Twisted Pair Wire

T +

19

T -

20

R +

21

R -

22

Signal Common

23

(Optional)

Host Computer

(rear view)

Series 945 #1

NOTE:

The Electronic
Industry Association
(EIA) RS-422A
standard recom­mends a maximum
4000 ft. total network
distance.

19
20
21
22
23

T +
T ­R +
R -

Signal Common

(Optional)

Twisted Pair Wire

DB-9 female

connector

(viewed from wire side)

R +
R -

Com

1

6

2

7

3

8

T -

4

9

T +

5

4

WATLOW Series 945

How to Use Data Communications

RS-423A Interface Pinouts (RS-232C Compatible)

1

945A-XXXX-B000

The RS-423A communications uses a three wire (full duplex) system. There is a
separate line for transmitting, a line for receiving data, and a line for signal common
between the computer and the Series 945. With RS-423A you can have only one
Series 945 control connected to a single computer or printer.

This diagram is a typical wiring example. The connections on the host computer
may vary depending on models. Refer to your computer user's manual for more
information.

Host Computer

(rear view)

RS-423A

Figure 2 ­RS-423A Interface,
Pin Designations.

R, and RLSD together.

and CTS together.
puter's user manual.

T

20

Jumper to Signal Common

21

R

22

Signal Common

945 #

23

DB-25 female

connector

(viewed from wire side)

DTR (Data Terminal Ready)

1

14
15
16
17
18
19
2 0

21
22
23
24
25

T

2

R

3

3

4

RTS (Request To Send)

4
5

CTS (Clear To Send)

6

DSR (Data Set Ready)

Com

7

RLSD (Received Line Signal Detector)

8
9
10

11
12
13

NOTE:

The Electronic
Industry Association
(EIA) RS-423A
standard recom­mends a maximum
50 foot total point­to-point distance.

How to Use Data Communications

WATLOW Series 945

5

EIA-485

1

EIA-485 Interface Pinouts

945A-XXXX-D000

The EIA-485 communications uses a two wire (half duplex) system. There are only
two lines, both lines used for transmitting and receiving. Only one device, the
computer or the control, can be speaking at a time. There is a 1 millisecond delay
requried for the Series 945 to go between transmission and receipt of data. With
EIA-485 you can have from one to thirty-two Series 945 controls connected to a
computer.

Figure 3 ­EIA-485 Interface, Pin
Designations.

Series 945 #

Series 945 #31

This diagram is a typical wiring example. The connections on the host computer
may vary depending on models. Refer to your computer user's manual for more
information.

Twisted Pair Wire

T+/R+

19

T-/R-

20

Signal Common

23

(Optional)

Host Computer

(rear view)

Twisted Pair Wire

T+/R+

19

T-/R-

20

Signal Common

23

#32

(Optional)

DB-9 female

connector

(viewed from wire side)

1

6

2

7

3

8

4

9

5

Com

T-/R-

T+/R+

T+/R+

T-/R-

NOTE:

The Electronic
Industry Association
EIA-485 standard
recommends a
maximum 4000 ft.
total network dis­tance.

6

WATLOW Series 945

Connecting the Control and the Computer

Remove power from both the Series 945 and your computer or printer before
connecting them together. This prevents noise or static interference from entering
the data communication lines. Assemble a cable and the appropriate wiring at your
computer or printer. Refer to the wiring on Page 4 through 6. As soon as you
connect the data communications line(s), you're ready to apply power to your
system.

How to Use Data Communications

A

A

(Up) RS-423A

(Up) RS-423
(Down) RS-422

(Down) RS-422A

A007-1830

How to Set the Hardware Protocol Switches

for 945A-XXXX-B000 Units Only

The RS-422/RS-423 switches are on the Communication Module Board (A007-

1830). Figure 4 shows the location of this board. You can select C1 for RS-423 or
C2 for RS-422 operation. Both switches must be set the same for the desired
protocol.

To change the position of a switch, remove the power from the Series 945 and turn
the front panel locking screw 90° counterclockwise. To remove the control chas-

Control Chassis - Top View

sis, grip the front panel bezel and pull it straight out from the control case. Set the
switches, C1 (towards you for RS-423) or C2 (away from you for RS-422) then
return the control chassis to the case. Be sure it is oriented correctly. Press firmly,
but gently, to seat the chassis. Secure the front panel locking screw and reapply
power.

Configuration

Figure 4 ­RS-422A/RS-423A
Switch Selection.

NOTE:

The Series 945
leaves the factory in
RS-423A operation (C1).

Network Connections

You can connect a data communication equipped Series 945 to any computer with
an RS-422A or RS-423A (RS-232C compatible) or EIA-485 serial interface. The
serial interface is the key. The IBM™PC® with an RS-232C serial output card,
for instance, will talk to a single RS-423A equipped Series 945. For a multiple 945
network with the same PC, you'll need an RS-232 to RS-422 converter to act as a
"bus," or multiple connection point.

Watlow recommends the Burr-Brown LDM 422 for that purpose. The address is:
Burr-Brown, Inc., 1141 West Grant Rd,. Suite 131, Tucson, AZ 85705, Phone:
[phone], Fax: [phone].

For EIA-485, we recommend the Black Box LD485A. Their address is: Black Box
Corporation, Mayview Road at Park Drive, Box 12800, Pittsburgh, PA 152421,
Phone: [phone].

Series 945 Comunication Parameters

To communicate with the Series 945, match the serial port settings of your com­puter with the available settings in the 945:

bAUd Rate = 300, 600, 1200, 2400, 4800, 9600 (choose one)
dAtA = 7o = 7 data bits and odd parity

7E = 7 data bits and even parity (choose one)

8n = 8 data bits and no parity
Start Bit = 1
Stop Bits = 1

How to Use Data Communications

WATLOW Series 945

7

Parameters

Setup Menu - Communications Parameters

Enter the Setup menu by pressing the UP/DOWN keys simultaneously for 3
seconds. The lower display shows the LOC parameter, and the upper display
shows its current level. All keys are inactive until you release both keys. You can
reach the LOC parameter from anywhere. This is only a listing and brief explana­tion of the parameters, refer to Pages 22 through 26 for a thorough explanation of
Statistical Process Control (SPC).

bAUd

dAtA

Prot

Addr

Log

LSL

USL

Baud: Represents the current baud rate for serial communications.
Range: 300, 600, 1200, 2400, 4800, 9600 Default: 1200

Data: Allows the user to select the data bits and parity for communication.
Range: 7 o = 7 data bits and odd parity 7E = 7 data bits and even parity

8 n = 8 data bits and no parity Default: 7 o

Protocol: Selects the communication protocol. Must be On for data logging to

occur. FULL = ANSI X3.28 2.2 - A.3 On = XON - XOFF

Range: FULL or On Default: FULL
Address: Selects the address device if Prot = FULL. Range: 0 to 31 Default: 0
Log: Selects the data logging function for a printout of the data. Appears if Prot =

On. For further expon on SPC, the parameters and printouts, see Page 22 - 26.

Range: OFF, tAbL, CHrt, SPCA, SPCd, SPCn Default: OFF
Lower Specification Limit: This value is the specified deviation below set point,

which statistically the process should not exceed. Appears if Prot = On and Log =
SPCA or SPCd. SPCA Range: rL to Lower USL -2°F/-1°C Default: rL

SPCd Range: 1 to 99 Default: 10
Upper Specification Limit: This value is the specified deviation above set point,

which statistically the process should not exceed. Appears if Prot = On and Log =
SPCA or SPCd.SPCA Range: rH to upper LSL +2°F/1°C Default: rL
SPCd Range: 1 to 99 Default: 10

tbS

Time Base: Selects the time in minutes over which 30 random samples are taken
for computing SPC values. Appears if Prot = On and Log = SPCA or SPCd.
Range: 1 to 60 Default: 5

LinE

Line: Selects the number of lines per page of data logged output. Match this
parameter to the number of lines per page your printer prints. After you select the
number of lines to print, a form feed character is sent to the printer, resetting the
top of the page. Range: 10 to 127 Default: 65

YEAr

Year: Select the current year for the data logging header. Appears if Prot = On
and Log = tAbL, CHrt or SPCA, SPCd, SPCn. Parameter resets to default after a
power interruption. Default: 92

Mon

Month: Select the current month for the data logging header. Appears if Prot =
On and Log = tAbL, CHrt or SPCA, SPCd, SPCn. Parameter resets to default after
a power interruption. Default: 01

dAY

Day: Select the current day for the data logging header. Appears if Prot = On and
Log = tAbL, CHrt or SPCA, SPCd, SPCn. Parameter resets to default after a
power interruption. Default: 01

HOUr

Hour: Represents the 24 hour time-of-day clock setting for minutes. Appears if
Prot = On and Log = tAbL, CHrt or SPCA, SPCd, SPCn. Parameter resets to
default after a power interruption. Range: 0 to 23 Default: 0

8

WATLOW Series 945

How to Use Data Communications

Minutes: Represents the 24 hour time-of-day clock setting for minutes. Appears
if Prot = On and Log = tAbL, CHrt or SPCA, SPCd, SPCn. Parameter resets to
default after a power interruption. Range: 0 to 59 Default: 0

Interval: Selects the time interval for the logging function. The logging interval is in
tenth of a minute increments. Appears if Prot = On and Log = tAbL, CHrt or
SPCA, SPCd, SPCn. Range: 0.0 to 60.0 minutes Default: 0.0

Setup

Min

Int

Tag: Selects what variables are to be transmitted out during the data logging

tag

function. Any combination of process, set point and alarms may be "tagged" for
logging. Appears if Prot = On and Log = tAbL.
P = Process S = Set Point A = Alarm Set Points

Range: PSA, PS -, P-A, P- -, -SA, -S-, --A, --- Default: ---

Setup Menu

Use this page as a master copy for your Series 945 data communications Setup
parameters. Do not enter any values here; make photocopies instead.

Table 1 ­Setup Menu
Prompts and
Descriptions.

Parameter Value Range Factory Default Appears If:

bAUd 300, 600, 2100, 2400, 4800, 9600 1200
dAtA 7 o = 7 data bits and odd parity

7E = 7 data bits and even parity
8 n = 8 data bits and no parity 7 o

Prot FULL = ANSI X3.28 2.2 - A.3 FULL

On = XON - XOFF

Addr 0 to 31 0 Prot = FULL
Log OFF, tAbL, CHrt, SPC OFF Prot = On
LSL SPCA = rL to Lower USL -2°F/-1°C rL Prot = On &

SPCd = 1 to 99 10 Log = SPCA, SPCd

USL SPCA = rH to Upper LSL +2°F/1°C rL Prot = On &

SPCd = 1 to 99 10 Log = SPCA, SPCd

tbS 1 to 60 5 Prot = On &

Log = SPCA, d, n

LinE 10 to 127 65 Prot = On & Log = tAbL

CHrt or SPCA, d, n

YEAr -- 92 Prot = On & Log = tAbL

CHrt or SPCA, d, n

Mon -- 01 Prot = On & Log = tAbL

CHrt or SPCA, d, n

dAY -- 01 Prot = On & Log = tAbL

CHrt or SPCA, d, n

HOUr 0 to 23 0 Prot = On & Log = tAbL

CHrt or SPCA, d, n

Min 0 to 59 0 Prot = On & Log = tAbL

CHrt or SPCA, d, n

Int 0.0 to 60.0 minutes 0.0 Prot = On & Log = tAbL

CHrt or SPCA, d, n

tag PSA, PS-, P-A, P--, -SA, -S-, --A, --- --- Prot = On & Log = tAbL

P = Process S = Set Point
A = Alarm Set Points

Operation Menu

This parameter follows the Aut parameter in the Operation menu. See Page 25 for
more information.

Control Limit Update: When YES is selected, it calculates and prints out control
limits according to the time base. If no is selected, the current control limit is
printed and no subsequent limits are printed. Range: YES or no Default: YES

How to Use Data Communications

CLUP

WATLOW Series 945

9