8400100.qxp

3/20/2006

3:18 PM

Page 62

900MB

SeriesThermocouple/Millivolt Input Module

Modbus/RS-485

Four
Discrete
Outputs
orLimit Alarms

Inputs (2)Four
Thermocouple
orDC Millivolt
Inputs

Outputs (4)Isolation

RS-485

Modbus10-36V DC
or 24V AC

PowerBusWorks® Modbus I/O

Inputs (2)924MB
Multi-Channel
Temperature
Control Modules
Thermocouple orMillivolt Input
Limit Alarms or
Discrete Outputs
Model
924MB: 4 input channels
Input
Four input channels:
Thermocouple (types J, K, T, R, S, E, B, N),±100mV DC
OutputFour output channels:
Open-drain MOSFETs (1A DC loads)
0 to 35V DC
Network Communication
Modbus-RTU high-speed RS-485
Power Requirement
10 to 36V DC,24V ACApprovals
CE marked. UL, cUL listed
Class I; Division 2; Groups A, B, C, D.

■ Description■ Special Features

This signal conditioner is a four-channel analog
input module with four discrete outputs. It filters
and linearizes thermocouple inputs while providing isolation between input, output, power, andnetwork circuits. Cold junction compensation
and upscale/downscale sensor break detection
are standard. AC and DC power sources are supported with nonpolarized, diode-coupled terminals.

■

Standard Modbus RTU protocol with high-speed
RS-485 communication (up to 115K bps)■

16-bit sigma-delta A/D yields 0.1°C resolution
and 0.5°C measurement accuracy■

Thermocouple linearization and sensor break
detection ensure reliable measurements■

Four discrete outputs enable local temperature
limit alarms or host-controlled on/off switching■

Heavy-duty 1A solid-state relays provide
dependable on/off control of industrial devices■

Self-calibration lowers maintenance costs by
reducing periodic manual calibration checks■

Watchdog timers provide a configurable
failsafe output state for use when hostI/O communication is lost■

Four-way isolation eliminates potential groundloops between power, input, output andnetwork circuitry■

Self-diagnostics monitor microcontroller activity
to detect operational failures (lock-up) and
execute a reset to restore communication

The programmable inputs accommodate eight
thermocouple types plus wide-range millivolt
signals. Flexible discrete outputs operate asalarms or on/off controllers. As limit alarms, eachdiscrete output can be configured with highand/or low setpoints exclusively tied to an analog
input channel. Alarm trips function without hostcommunication enabling low-cost stand-alone
alarms as well as local backup for the primarycontrol system. Otherwise, on/off control isbased on commands issued by the host system.
Combining flexible transmitter functions, mixed
signal I/O, alarm support, and a network interface in a single package, makes this instrument
extremely powerful. Multi-channel design adds
cost-efficiency and allows high-density mounting.
Plus, safe, rugged construction makes thesemodules reliable for use in both control roomand distributed field I/O applications. Custom
module configurations are also possible (consultfactory for details).

Tel: 248-295-0880 e-mail: sales@acromag.com www.acromag.com
8401-003

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ModbusI/O■ Performance■ DC Millivolt Input

LED Indicators
LEDs indicate power, status, and discrete level/alarm.

■ General Input

Millivolt Input Ranges±100mV DC.

Resolution■ Power and Isolation

Millivolt Input Accuracy±100mV DC input: 0.1%.
Thermocouple input: 0.1°C (0.18°F).

Power Requirements±0.1% of input range.

10 to 36V DC,
22 to 26V AC.

Ambient Temperature Effect■ Discrete Output

Better than ±0.005% of input span per °C, or±1.0uV/°C, whichever is greater.

Output TypeSupply Current

Four independent open drain MOSFET switches with acommon return that operate as low-side switches.

Supply10V DC
24V DC
24V AC

Noise Rejection
Normal mode: 40dB @ 60Hz, typical.
Common mode: 140dB @ 60Hz, typical.

Output Voltage Range
0 to 35V DC, 1A DC maximum for each output.
External voltage source required.

Input Filter Bandwidth-3dB at 3Hz, typical.

Output ON Resistance

Input Conversion Rate

0.15 ohms maximum.

90ms per channel.

Operation

Thermocouple Input Ranges
Thermocouple type user-configured. Type selected
applies to all channels. Signal linearization, cold-junction compensation, and open circuit or lead break
detection are included.
TC °C Range (°F Range)
AccuracyJ -210 to 760°C (-346 to 1400°F)±0.5°CK -200 to 1372°C (-328 to 2502°F)±0.5°CT -260 to 400°C (-436 to 752°F)±0.5°C
R -50 to 1768°C (-58 to 3214°F)±1.0°CS -50 to 1768°C (-58 to 3214°F)±1.0°CE -200 to 1000°C (-328 to 1832°F)±0.5°CB 260 to 1820°C (500 to 3308°F)±1.0°CN -230 to 1300°C (-382 to 2372°F)±1.0°C
Note 1: Accuracy is given with CJC switched off.
Relative inaccuracy with CJC enabled may increaseby ±0.5°C.

Thermocouple Break Detection
TC sensor failure can be configured for either upscaleor downscale. Selection applies to all channels.

Digital outputs are set to their OFF state following asoftware or power-on reset. Outputs can optionallybe set to user-defined states following a watchdog
timeout. Watchdog timeout output control takes
precedence over limit alarm control. Alarm control
takes precedence over host control.

Output Response Time
4.1ms typical, from receipt of command to gate
transition of the output MOSFET.
■ Communication

Supported Modbus Commands
The command/response protocol for communicatingwith this module adheres to the Modbus/RTU standard
for the following Modbus Functions.
Read CoilRead Holding Registers
Read Input Registers
Force Single Coil
Preset Single Register
Force Multiple Coils
Preset Multiple Registers
Report Slave ID
Reset Slave

IN1-924MB-0900
Thermocouple/millivolt input module
900C-SIP
Configuration Software Interface Package(includes software CD-ROM for Windows,
RS-232/485 converter, and RS-485/three-wire cable)
4001-095
USB-to-RS232 adapter
TBK-B01
Optional terminal block kit, barrier strip style, 2 pcs.
(Does not include terminal block for input wiring.)
TBK-S02
Optional terminal block kit, spring clamp style, 2 pcs.
(Does not include terminal block for input wiring.)
PS5R-VB24
Power supply (24V DC, 2.1A)

OUT0COMCOM
DBA

MECHANICALRELAY INTERFACE+

DIGITAL OUTPUT

36 35 34 33 32 31

IN3-RTNOUT1DPWR

IN3+

RS485

IN-

IN2-

CJC-1 INPUTS 2,3

21 22 23 24 25 26

IN+ANALOGINPUTOUT2UP TO
35V DC

TB4

TB1

TB1/TB2

IN2+

OUT3TB3

TB2

VOLTAGE INPUT

RTN

46 45 44 43 42 41

IN-

IN0IN1+

DIGITAL OUTPUTS

IN+IN0+

CJC-0 INPUTS 0,111 12 13 14 15 16

ANALOGINPUT

TB1/TB2

NETWORKCOMMUNICATIONTB3TB2-■ Ordering
Information

TB4

TB1

TC INPUTVOLTAGESOURCE

1500V AC for 60 seconds or 250V AC continuous.
4-way isolation between input, network, power anddiscrete I/O circuits. Inputs are isolated channel-tochannel for common mode voltage to ±5V DC.

DIGITAL OUTPUT CONNECTIONSANALOG INPUTCONNECTIONS+Isolation

AC/DC
POWER
10 TO 36V DC
OR 24V AC
NON-POLARIZED

OUT
RTN

TB4

RTN

RTN
OUT 3OUTOUT 2
DIGITAL OUTSHARES
RETURNRTN
OUT 1OUT 0Tel: 248-295-0880 e-mail: sales@acromag.com www.acromag.com
8401-003

BusWorks® Modbus I/O■ Thermocouple Input

Current Draw
100mA maximum
45mA maximum
85mA rms maximum

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900MB

Series

900MB Series Technical Diagrams
TB4

TB3

Acromag

DFTB
A

DD

TB3

TB1

2.34(59.4)

BusWorks® Modbus I/O

PWR

TB2

2 3

CL

RS485

3.75(95.3)

0 1

36 35 34 33 32 31

TB4

STCOMCOM

46 45 44 43 42 41

RUN

4.68(118.9)"T" Rail Din Mounting
Din EN 50022, 35mm

11 12 13 14 15 16

21 22 23 24 25 26

TB2

TB13.90(99.1)

1.05(26.7)
NOTE: ALL DIMENSION ARE IN INCHES (MILLIMETERS)

4.35(110.5)

PERSONAL COMPUTER
W/ WINDOWS 95/98 OR NT
RS-232 SERIAL
PORT CONNECTOR
AT BACK OF PC

PC RUNNING
ACROMAGMODBUS CONFIG
SOFTWARE

INSTALL MODBUSCONFIGURATIONSOFTWARE

RS-232 TO RS-485 CONVERTERMODEL 5034-214

CONNECT THE RS-232
SIDE OF CONVERTERTO THE PC

CAUTION: DO NOT CONNECT THE
CABLE DIRECTLY TO THE PC WITHOUTTHE CONVERTER, OR DAMAGE TO
THE MODULE MAY RESULT.

CABLE 5034-202

CONNECT THE RS-485
SIDE OF CONVERTERTO THE CABLE

900C-SIP COMMUNICATION CONNECTIONSCBACONNECT WIRES AS SHOWNCOM DTB4TB4Acromag
RUNRED

RS-485DB

BLACKDCGREENCOMREFER TO THE USER'S MANUALTHAT CAME WITH YOUR MODULETO COMPLETE THE MODULE'S
POWER AND I/O CONNECTIONS

TB2

TB1COLORA

PWR

ANY 900MB MODULE

TB1

RA

STATUS LED FLASHES IN
DEFAULT MODE.

B

RS485

DDEFAULT MODE SWITCH PUSH FOR DEFAULT MODE.

DTB33WIRE

36 35 34 33 32 31COM

246 45 44 43 42 41

TB3COM

1RUN/PWR LED (GREEN)
STATUS LED (YELLOW)TB4STDFT0D11 12 13 14 15 16

21 22 23 24 25 26

TB1

TB2

Tel: 248-295-0880 e-mail: sales@acromag.com www.acromag.com
8401-003

(This page intentionally left blank.)

Modbus

I/O■ Performance■ General■ Discrete Inputs(901 & 903 models only)
Input Type

5.6K ohm pull-up resistor SIPs are installed in sockets
at each port (four-channels per port).

I/O Pull-ups and Socket

12 active-low, buffered inputs, with a common connection. Inputs include transient suppression devices
and series connected 100K ohm resistors, plus diodeover-voltage clamps to the internal +5V supply.

Excitation (per port)

External excitation voltage for each four-channel port
is limited to 35V or less.

Supported Modbus Commands

0 to 35V DC, maximum.

Input Current

293µA, typical at 35V DC.

Input Signal Threshold

TTL compatible with 100mV of hysteresis, typical.
Low-to-High threshold is 1.7VDC, High-to-Low is
1.6VDC, typical. Limited to TTL levels of 0.8VDC(max. LOW level) and 2.0VDC (min. HIGH level).

Input Resistance

100K ohms, typical.

LED Indicators

Input Hysteresis

LEDs indicate power, status, and discrete level.

100mV DC, typical.

Power Requirements
10 to 36V DC,
22 to 26V AC.

■ Discrete Outputs(902 & 903 models only)
Output Type

12 independent, open-drain, DMOS MOSFET switcheswith a common source connection that operate as
low-side switches.

Output Voltage Range

0 to 35V DC max. (0 to 500mA/channel continuous).
External voltage source required.

Output ON Resistance
0.28 ohms maximum.

Models901MB-0900
Discrete input module
902MB-0900
Discrete output module
903MB-0900
Discrete input/output module

Accessories

900C-SIP
Configuration Software Interface Package(includes software CD-ROM for Windows,
RS-232/485 converter, and RS-485/three-wire cable)
4001-095
USB-to-RS232 adapter
TBK-B02
Optional terminal block kit, barrier strip style, 4 pcs.
TBK-S02
Optional terminal block kit, spring clamp style, 4 pcs.
PS5R-VB24
Power supply (24V DC, 2.1A)

Supply Current
Supply10V DC
24V DC
24V ACCurrent Draw
130mA maximum
54mA maximum
95mA maximum

Isolation

1500V AC for 60 seconds or 250V AC continuous.
3-way isolation between I/O, network, and power
circuits.

Output Response TimeOptional terminal blocks: barrier strip (left) andspring clamp (right). Cage clamp terminal is standard.

Force Single Coil: Output updates within 250µs ofreceipt of a command.
Force Multiple Coils: First coil updates in 250µs,
followed successively by additional coils every 180µs.
DIGITAL INPUT CONNECTIONS (ACTIVE LOW)

DIGITAL OUTPUT CONNECTIONS+ 12-24V DC,

CH 3
RTN

CH 0
CH 1
CH 2
CH 3

INTERNAL INPUT
PULL-UPS ARE PRESENT

CH 7
RTN

CH 8
EXC3COMCOM
DDBA100K

TB3

TO OTHER 3CHAN OF PORTDIGITALI/O

5-35VONOFF

NETWORKCOMMUNICATION

RTN

AC/DC
POWER
10 TO 36V DC
OR 24V AC
NON-POLARIZED

TB1
EXC1OUTCH 0
DIGITAL I/O
SHARES
RETURNRTN

CH 1CH 2CH 3
RTN

RTN

Tel: 248-295-0880 e-mail: sales@acromag.com www.acromag.com

8401-003

V
I/O

902MB/903MB

TB3

EXC1CH 6CH 936 35 34 33 32 31

TB2

TB1

CH 5

PWR

RTN

CH 4

CH10

TB4

RS485

DIGITAL
I/O

EXC2

DIGITAL IN or OUT

21 22 23 24 25 26

INP
SPST
RELAY

RTN
CH11903MB shown.
901MB & 902MB
are similar.

TB2

TYPICAL

RTN

CH 2TB1

RTN

CH 1TB4EXC

DIGITAL
I/O

CH 046 45 44 43 42 41

INP

11 12 13 14 15 16

RTN

EXC1

DIGITAL IN or OUT

TB1
DIGITAL IN or OUT

EXC
INP

DIGITAL I/O
SHARES
RETURN

LOAD+5V+5V

INP

EXC

903MB

5V TTL LOGIC - INPUT CAN BE PULLEDUP INTERNALLY OR EXTERNALLY

BusWorks® Modbus I/O

The command/response protocol for communicatingwith this module adheres to the Modbus/RTU standard
for the following Modbus Functions.
Read Coil (Output) Status
Read Input Status
Read Holding Registers
Force Single Coil (Output)
Preset Single RegisterReset Slave
Force Multiple Coils (Outputs)
Preset Multiple Registers
Report Slave ID

Input Signal Voltage Range■ OrderingInformation

Accessories
Model 4001-095 USB-to-Serial Adapter
PERSONAL COMPUTERRUNNING WINDOWS
98/ME/2000/XPHOSTUSBTO HOST USB PORT

USB MALE

HOST PC RUNNING
ACROMAGCONFIGURATIONSOFTWARE

4001095
USB SERIAL CONVERTERLEDRS232
DB9P

6 FEET OF CABLE

Simplifies configuration of Acromag I/O Modules ◆ Enables configuration via USB port

Description

Performance Specifications

Ordering Information

This device is a USB-to-serial adapter that you
can use to communicate with many Acromag I/O
products for setup and re-configuration for yourapplication.

USB Specification
Version 1.1
Data rate
Up to 115.2Kbps
Environmental Standards
RoHS-compliant
Basic Power Consumption
150mA
PC Requirements
Windows® 7 and newer.

NOTE: For more information visit www.acromag.com.

Key Features & Benefits■

Connects to I/O modules via USB(other adapters may be necessary)■

Complete RS232 control signals■

Conforms to USB Specification, Version 1.1■

USB-powered■

Cable length, 6 ft., UL approved

Adapters
4001-095
USB to serial adapter. Includes driver CD and manual.
5030-913
Serial port adapter. DB9S connector to RJ11 jack.
5034-202
RS-485 to 3-wire cable converter and cable, DB-9M to3 x 12AWG RS-485 cable, 8 ft.
5032-787
RS-232 to 151T transmitter configuration device
converter and cable, 6 ft.
5034-214
Non-isolated RS-232 to RS-485 Serial Port Converter,
DB-9F to DB-9F.

CablesIntelliPack 800x Series
Adapter and Cable
9-PIN CONNECTOR (DB9S)

INTELLIPACKSERIAL ADAPTER

RJ11 JACK(6 CONDUCTOR)

5030-902
Cable. 6 feet long with RJ11 plug at each end.

RJ11 PLUG(6 CONDUCTOR)MODEL 5030-902(6 feet long)MODEL 5030-913

900MB Modbus Series
Adapter and Cable
RS232 TO RS485 SERIALCONVERTER(MODEL 5034-214)

CABLE 5034-202

RS-485

RS-2325034-202

CDB9 FEMALE

DB9 FEMALEBA

DB9 MALECOM D D

Tel: 248-295-0880 ■ sales@acromag.com ■ www.acromag.com ■ 30765 S Wixom Rd, Wixom, MI 48393 USA
Bulletin #8400-572B

All trademarks are property of their respective owners. Copyright © Acromag, Inc. 2019. Data subject to change without notice. Printed in USA 5/2019.