E-M-HP21-V1_21
Rotronic AG
Bassersdorf, Switzerland
Document code
Unit
HygroPalm HP21 hand-held indicator:
User Guide
Instruction Manual
Document Type
Page
3
of 14
Document title
© 2009-2010; Rotronic AG E-M-HP21-V1_21
Applicability:
This manual is valid for the HP21 with firmware version 1.x, where 1.x can be 1.0, 1.1 etc. Changes to the last
digit of the version number reflect minor firmware changes that do not affect the manner in which the
instrument should be operated.
1
Overview
The HP21 is a highly accurate hand-held indicator that displays relative humidity, temperature and the dew or
frost point. The HP21 is perfect for spot checking HVAC installations, manufacturing and storage areas, and
generally for all ambient air measurement within the temperature range of -10 to 60°C (14 to 140 °F). The
HP21 operates with a regular 9V alkaline battery.
Based on the ROTRONIC AirChip 3000 digital technology the HP21 offers the following user functions:
User configurable settings
Calculation of the dew or frost point
Humidity temperature calibration and adjustment
Simulator mode
Automatic humidity sensor test and drift compensation
Sensor failure mode
Data recording
The ability for the user to easily update the AirChip 3000 firmware means that the HP21 can be kept up-to-
date regarding any future functionality improvement.
2
General description
2.1 Power supply
The HP21 operates with a regular 9V alkaline battery
2.2 Measured parameters
The HP21 measures relative humidity with a ROTRONIC Hygromer
®
IN1 capacitive sensor and temperature
with a Pt100 RTD.
2.3 Calculated parameters
Using the ROTRONIC HW4 software, the HP21 can be configured by the user to calculate either the dew
point or the frost point.
2.4 Sensor protection (dust filter)
The HP21 is supplied with a Polyethylene filter to protect the sensors against dust particles and high air
velocity.
