Indicators on the display, Service port, Connecting with an mi70 indicator – Vaisala HMW90 User Manual
Page 39: Caution

Chapter 4 _________________________________________________________________ Operation
VAISALA ________________________________________________________________________ 37
Indicators on the Display
Indicator Position on Screen Meaning
Top right
Is shown when relay contacts are open
(HMW93 and TMW93 only).
Top right
Is shown when relay contacts are closed
(HMW93 and TMW93 only).
Top left
Is shown when an MI70 Indicator is
connected to the service port.
Bottom left
Is shown if an error is active. The error
message is written after the indicator. See
section Error Messages on the Display on
page 76.
Service Port
You can connect to the service port on the HMW90 series transmitters
using a PC or an MI70 indicator. The MI70 indicator is the hand-held
display device that is included with, for example, the Vaisala
HUMICAP
®
Hand-Held Humidity and Temperature Meter HM70.
CAUTION
The service port is not galvanically isolated from the rest of the
transmitter electronics. Connect only equipment with a floating power
supply (not grounded) to the service port. If you connect a device that is
grounded to a different potential than the transmitter’s power supply, you
will affect the accuracy of the transmitter’s analog outputs. You may
even affect the transmitter’s functionality or cause damage to the
transmitter.
Connecting With an MI70 Indicator
When connecting using an MI70 indicator, use the connection cable for
HM70 hand-held meter (Vaisala order code 219980). The following
functionality is available when using the MI70:
- Standard MI70 functions such as viewing, logging, and graphs of
measurement results.
- Calibration and adjustment fuctions for the transmitter. For more
information, see section Adjustment Using an HM70 on page 70.
- Setting of the pressure compensation value for humidity measurement
(Environment menu in the MI70).