Analog output signals, Digital outputs, E-m-hf5-v2_12 – ROTRONIC HF5 User Manual

Page 7: 4 analog output signals, 5 digital outputs

E-M-HF5-V2_12

Rotronic AG
Bassersdorf, Switzerland

Document code

Unit

HygroFlex HF5 Humidity Temperature
Transmitters: User Guide

Instruction Manual

Document Type

Page

7 of 36

Document title

Mixing ratio by weight (R)

Vapor concentration at saturation (Dvs)

Vapor partial pressure (E)

Vapor saturation pressure (Ew)

Note: some of the above parameters depend on the value of the barometric pressure. Using the ROTRONIC
HW4 software, a fixed barometric pressure value can be specified. For instructions see the following HW4
manual: E-M-HW4v3-F2-005

3.4 Analog output signals

Parameter:

With the ROTRONIC HW4 software any of the two analog output signals can be made to correspond to one of
the following:

Relative humidity
Temperature
Calculated parameter

Any output can also be disabled.

Output Scale:

The scale of each analog output can be set within the numerical limits of -999.99 and 9999.99. The D/A
converters used to generate the analog output signals feature a 16-bit resolution.

Signal Type:

Both analog outputs provide the same type of signal. With the exception of the HF52 (alwa

ys 4…20 mA), the

type of signal can be selected with the ROTRONIC HW4 software to any of the following:

0…20 mA, 4…20 mA, 0…1V, 0…5V or 0…10V (see 4.3).

3.5 Digital outputs

Models with a digital output can simultaneously transmit 3 parameters: relative humidity, temperature and
calculated parameter

a) RS-485 serial interface

Some models of the HF5 are equipped with a RS-485 serial interface. This can be used to connect together
up to 64 devices in a multi-dropped arrangement. In principle, an unlimited number of such networks can be
monitored with the HW4 software, but each RS-485 multi-drop network is limited to 64 devices. The HF5 can
be used either as a slave or a master, without special configuration. The master is automatically the device
that is directly connected to a PC by means of a USB port or Ethernet (TCP/IP) port.

RS-485 Compatibility: The communication protocol used by the HF5 and other AirChip 3000 products is not
compatible with the protocol used by the previous generation of ROTRONIC instruments. Do not connect
legacy products and AirChip 3000 products to the same RS-485 multi-drop network.

b) USB or Ethernet interface

Some models of the HF5 are available with a USB or Ethernet interface in addition to the RS-485 interface. In
this case the protection grade of the HF5 enclosure is no longer IP65 / NEMA 4 rated.