Vaisala GMM112, GMW115 QUICK REFERENCE GUIDE

QUICK REFERENCE GUIDE

Vaisala CARBOCAP® Carbon

Dioxide Module GMM112 and

Transmitter GMW115

ELECTRICAL CONNECTIONS

mA Signal 4 ... 20 mA
V Signal (+) 0 ... 10 V
0 Signal (-)
B RS-485 Signal B
A RS-485 Signal A
0 Power supply (-)
24V Power supply (+) 24 VDC/VAC

See Figure 3 for wire terminals.

Powering

Figure 2 Connection of Single AC supply to Several Transmitters

MOUNTING AND DIMENSIONS

Dimensions

mA

mA

V

Ø3.2

V

0

0

B

B

A

A

0

0

24V

24V

96

25656

0601-002

The products require a nominal 24 VDC/VAC power supply
maintaining a voltage of 18 ... 30 VDC or 20 ... 26 VAC for all
load conditions and all mains voltages. Although the power input
includes a half-wave rectifier, it is recommended to use a DC
supply to avoid current peaks.

Connections to 24 VAC Power Supply

Connecting more than one transmitter to a single 24VAC
transformer forms a common loop and increases the risk of a
short-circuit. Therefore, a separate floating supply for each
transmitter is recommended (see Figure 1).

If several

transmitters share a common transformer, the phase (~)
must always be connected to the 24 V connector in each
transmitter (see Figure 2).

Figure 3 GMM112 Module Connections and Dimensions

30

60

66.3
60

0601-004

2

4.

Ø

– GMM112 compact diffusion

aspirated CO

module for OEM

2

applications

– GMW115 CO

transmitter for wall

2

mounting

– Measurement range 0 ... 2000 ppm or

0 ... 5000 ppm CO

2

– Ideal for HVAC applications

© Vaisala 2010. All rights reserved.

*M210746EN*

3

85.2

83.4

0601-001

Figure 1 Connection of Separate AC Supplies (Recommended)

25.8

85.

60

66.7
124

1

.

2

R

R3

.

5

84

0601-005

120.9

Figure 4 GMW115 Transmitter Dimensions

Mounting the GMW115 Transmitter

Mount the back plate onto a wall using screws. Make sure the
back plate is mounted in with the same orientation as in Figure 4.

GMW115 Co

ver Opening/Closing

0601-006

Figure 5 Opening the GMW115 Cover

0601-007

Figure 6 Closing the GMW115 Cover

SERIAL COMMUNICATION INTERFACES

The modules support RS232 or RS485 communication. RS232 is set as
factory default. The RS485 interface is selected by serial command. The
communication settings for both interfaces are: 9600, N, 8, 1.

RS485 Interface

The interface is non-isolated two-wire interface with no internal bus
termination. If termination is needed, use RC termination (100 Ω resistor
in series with 1 nF capacitor) at both ends of the bus. See serial
commands list below to activate the RS485 interface.

RS232 Interface

Use the RS-232 interface for setting the operating parameters. The
connection cable between PC and module (a serial COM adapter for
maintenance purposes) is available from Vaisala (order code:
19040GM).

Visit our Internet pages at www.vaisala.com

SERIAL COMMANDS

Serial commands are the same for RS232 and RS485 interface.
<cr> stands for pressing ENTER.

Polling command for CO

measurement (ppm):

2

SEND <cr>

Setting the interval for the RUN (continuous output) mode:

INTV X Y<cr>

X = 0 (default) ... 255
Y = S/MIN/H

Starting the continuous mode printing:

R<cr>

Stopping the continuous mode printing:

S<cr>

Saving the parameters into the memory:

SAVE<cr>

Enabling/disabling the RS485 interface:

RS485 X<cr>

X = ON/OFF

Changing the operation mode:

SMODE X<cr>

X = STOP (default) / RUN / POLL

Giving the device address:

ADDR X<cr>

X = 0 (default) ... 99

Opening the polling line:

OPEN addr<cr>

addr = 0 (default) ... 99

Closing the polling line:

CLOSE<cr>

SERVICE, CALIBRATION AND ADJUSTMENT

These products are designed to operate their lifetime without
maintenance The transmitters are calibrated before shipping from the
factory. For technical questions, contact the Vaisala technical support; by
e-mail [e-mail]

Repair and calibration services are provided by Vaisala Service Centers:

, or by fax [phone].

TECHNICAL DATA

Property Description / Value
Performance

Measurement ranges 0 ... 2000 ppm CO

0 ... 5000 ppm CO2

Measurement accuracy
(incl. repeatability, non-

±(2 % of range + 2 % of

reading)
linearity and calibration
uncertainty)

Long-term stability ± 5 % of range / 5 years
Response time 1 min
Temperature dependence of

reading
Pressure dependence of

reading

-0.35 % of reading / °C

(typical)

+ 0.15 % of reading / hPa

(typical)
Warm-up time 1 min
10 min full specification
Product lifetime > 10 years
Operating environment
Operating temperature

-5 … +45°C

range
Operating humidity range 0 ... 85 %RH
Operating pressure range 700 hPa ... 1200 hPa
Inputs and outputs
Operating voltage 24 V (±20 %) AC/DC
Power consumption < 2 W
Connections Screw terminals, wire size

0.5 ... 1.5 mm

Outputs

analog 0 ... 10 V, 4 ... 20 mA
serial RS-485, 2-wire, non-isolated

Recommended external
load

current output < 500 Ω
voltage output > 1 kΩ

Electromagnetic
compatibility

EN61326-1:

Generic Environment
Materials

2

2

Weight GMM112: 34 g
GMW115: 105 g
Housing material ABS plastic

GUARANTEE

Vaisala issues a guarantee for the material and workmanship
of this product under normal operating conditions for two (2)
years from the date of delivery. Exceptional operating
conditions, damage due to careless handling and
misapplication will void the guarantee.

Ref. M210746EN-E

N17728