PCE Instruments PCE-HT 422 Users guide

PCE Americas Inc.
1201 Jupiter Park Drive
Suite 8
Jupiter
FL-33458
USA
From outside US: +1
Tel: [phone]
Fax: [phone]
[e-mail]

www.pce-instruments.com/english

www.pce-instruments.com

PCE Instruments UK Ltd.

Southpoint Business Park

Hampshire / Southampton

United Kingdom, SO31 4RF

From outside UK: +44

Tel: [phone]

Fax: [phone]

[e-mail]

ENVIRONMENTAL DATA LOGGER

P

CE-HT 422

Unit 11

Ensign way

USER’S MANUAL

Contents

1. Application.......................................................................................................................................3

2. What is included...............................................................................................................................4

3. Basic requirements, operational safety.............................................................................................4

4. Fitting...............................................................................................................................................5

4.1. Installation.................................................................................................................................5

4.2. External connections diagram...................................................................................................5

5. Operation..........................................................................................................................................6

5.1. Messages after Switching the Supply on..................................................................................6

5.2. Functions of the button..............................................................................................................7

5.3. Connection of the device – configuration.................................................................................8

5.4. Functions of the monitor...........................................................................................................9

5.6. Ethernet 10/100-BASE-T........................................................................................................11

5.6.1. Connection of 10/100 BASE-T interface.........................................................................12

5.6.2. Ethernet interface default parameters...............................................................................13

5.6.2.1. Changing the parameters of Ethernet interface.........................................................14

5.6.3 Web Server........................................................................................................................14

5.6.3.1 General view...............................................................................................................15

5.6.3.2. Selection of Web server user.....................................................................................17

5.6.3.3. Messages to the user..................................................................................................18

5.6.3.4. Access to the archive file through the web server.........................................................19

5.6.3.5 Logic alarms..................................................................................................................20

5.6.4 FTP Server........................................................................................................................21

5.6.4.1 Selection of FTP user.....................................................................................................22

5.6.5 E-mail service.......................................................................................................................23

5.6.6 Modbus TCP/IP.....................................................................................................................25

5.6.6.1. Description of implemented functions.........................................................................26

5.6.6.2. Map of registers.............................................................................................................26

5.6.6.3. Read-only registers ......................................................................................................27

5.6.7 MQTT Protocol.....................................................................................................................28

5.7. Firmware upgrade....................................................................................................................29

5.8. Measured values archiving......................................................................................................30

5.8.1. The monitor memory structure.........................................................................................30

5.8.2. Configuration of archiving...............................................................................................31

5.8.3. File system internal memory............................................................................................31

5.8.4. Structure of archive files..................................................................................................32

5.5. Description of PCE-HT 422 monitor reading field..................................................................10

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Ordering code.................................................................................................................................37

6. Technical data

7.

.......................................................................................................................34

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● measurement, display and archiving of ambient temperature, relative humidity, dew
point, absolute humidity, illuminance, total volatile organic compounds (TVOC),
CO2 concentration

● signaling of exceeding set alarm values

● programming logic alarm outputs with reaction to the selected input value.

● real-time clock function with clock supply support in case of the monitor power

failure

● registration of input signals in programmed time

● interface RS485
◦ protocol: Modbus RTU

● Ethernet 10/100 BASE-T

◦ protocol: Modbus TCP/IP, HTTP, FTP, MQTT

◦ services: web server, ftp server, DHCP client, SMTP client,

Values measured and calculated by the monitor:

 Temperature,
 relative humidity,
 dew point,
 absolute humidity,
 wet bulb temperature,
 saturated vapor pressure,
 enthalpy
 illuminance
 total volatile organic coumpounds (TVOC)
 CO2 concentration.

All quantities and configuration parameters are available through the embedded Web
server, if the parameter is not visible, set it in the tab Settings-> registers on the website.

1. Application

PCE-HT 422 monitor is designed for continuous measurement and

conversion of selected environmental parameters into a digital form (prot. Modbus
TCP/IP, Modbus RTU , HTTP). The monitor programming is possible with the
built-in web server. The monitor has an LCD display field with 2x16 characters. The
device allows you to send e-mail messages informing about the current environmental
parameters as well as events that cause exceeding the alarm values. The monitor is
powered via Ethernet - PoE (Power Over Ethernet) or standard DC jack.

Features of PCE-HT 422 monitor:

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1 pc.

1 pc.

3. Basic requirements, operational safety

In terms of operational safety, the monitor meets the requirements of EN 61010-1.

Safety instructions

● The assembly and the installation of the electrical connections may be carried out
only by a duly qualified electrician.

● Before turning on the monitor verify the connections.

● The monitor is intended for installation and use in industrial electromagnetic

environments.

● A switch or a circuit-breaker should be installed in the building or facility. It should
be located near the device, easily accessible to the operator, and suitably marked.

Fig. 1. View of PCE-HT 422 monitor

2. What is included

● PCE-HT 422 monitor

● User’s manual

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4. Fitting

4.1. Installation

Fig. 2 Location of mounting holes

4.2. External connections diagram

The monitor has 3 external slots:

- Ethernet port 10/100 base-T

- DC power socket ɸ5.5 / 2.1 mm

- RS485 interface disconnectable socket

and 1 button to reset the device to the standard parameters - "Reset"

PCE-HT 422 monitor is mounted on a wall using a screw connection. The

monitor housing consists of an upper and a lower part.

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5. Operation

After wiring, mounting and powering the monitor is ready to work with factory

settings. The monitor can be programmed using the built-in web server, free eCon
software or through access to MODBUS registers.

The following parameters can be programmed in the monitor:

• Ethernet interface settings,

• Modbus settings,

• Archive settings,

• alarm settings,

• SMTP client settings - e-mail (only as unencrypted connection)

• MQTT settings

• system settings.

Caution: Do not remove the cover of the sensor as this may damage the device!

5.1. Messages after Switching the Supply on

After power is turned on the display shows the device and the manufacturer’s name

and software version. After about 4s the serial number of the device is displayed and after

subsequent 4s the IP address in the network, if the device has been connected to Ethernet

network - the address can be static or obtained from DHCP server.

Fig. 3. View of the upper part of PCE-HT 422 monitor

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- restoring factory parameters - after pressing and holding the button for 10 seconds;

Note: each successive restoring of factory parameters enables or disables the service of

obtaining network address from a DHCP server, i.e. if the DHCP service is enabled and

restoring the factory parameters will be forced , the DHCP service will be disabled (you will

be informed about the change by a message on the display) and default static IP address

will be assigned to the device: 192.168.1.19 (subnet mask: 255.255.255.0), another

request for restoring the factory parameters will enable the DHCP server service -

the network parameters will be obtained dynamically from the server;

- displaying the current IP address of the monitor – occurs after a short press

of the button – about 1 sec.

Fig. 4. Startup messages of PCE-HT 422 monitor

5.2. Functions of the button

The device contains one physical button for restoring the factory settings or

displaying the current IP address of the monitor. This button is located on the connector

panel – fig. 3.

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a) message about the monitor operation with DHCP
client enabled – the displayed IP address is the current
address of the monitor acquired from DHCP server;

b) message about the work of the monitor with disabled
DHCP client service - the displayed IP address is the
current address of the monitor set manually or the default
address (after restoring the default parameters); in order

5.3. Connection of the device – configuration

Configuration of the device is possible through free e-CON software, available on the
manufacturer's website (https://www.pce-instruments.com/english/download-win_4.htm).
Access to most configuration parameters is also available from the device's website via
the embedded HTTP server.

5.3.1. Connection of the monitor to the network equipped with a DHCP server

The easiest way to connect the PCE-HT 422 monitor to the Ethernet network is to

use an existing DHCP server in the network, which assigns the communication
parameters to the devices connected, i.e. IP address, subnet mask, gateway, DNS
address. In order to use the automatic configuration with DHCP server, make sure the
monitor is running with DHCP client service enabled - to do this, switch on the power of
the monitor and observe the initial messages:

to obtain the address from the DHCP server, restore the monitor to the factory parameters,
point 5.2, and restart the device - then a) message should be displayed with the IP
address obtained from the DHCP server.

In order to further configure the device a computer (tablet, phone) must be

connected to the same Ethernet network (also with DHCP client enabled - automatic
acquisition of IP address), open a web browser and in the browser address field type the
IP address displayed by PCE-HT 422. This will display the login screen to log the web server
that will allow further configuration - sign up to the administrator account, p. 5.6.3.2.

After gaining access to the full configuration we recommend that you disable the

DHCP client, leaving the acquired network parameters unchanged – IP address, subnet
mask, gateway, DNS address will be stored as static parameters.

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5.3.2. Connecting the monitor to the network without using DHCP server

In order to use static configuration of network parameters, make sure the monitor is
running with the DHCP client service disabled - to do this switch on the power of the
monitor and observe the initial messages:

a) message about the monitor operation with DHCP client
service enabled – the displayed IP address is the current
address of the monitor acquired from DHCP server;

to set the a static IP address factory parameters should be
restored, p. 5.2, and the device should be restarted – then a message should be displayed
b) with the static default IP address.

b) a message about the monitor operation with disabled
DHCP client service - the displayed IP address is the current
address of the monitor set manually or the default IP
address (after restoring the default parameters), if the
displayed address is different from 192.168.1.19 the factory

defaults should be restored twice, p. 5.2;

In order to further configure the device a computer (tablet, phone) must be
connected to the same Ethernet network (or directly to the monitor) and the automatic
acquisition of network parameters must be disabled. Then, the static parameters
corresponding to the default network parameters of PCE-HT 422 must be manually
entered into the computer (tablet, phone p. 5.6.2 (the same subnet mask and any IP
address from the pool 192.168.1.X except for the address 192.168.1.19
assigned by default to PCE-HT 422). After the connection, open your web browser and
type in the address field of the browser the default IP address 192.168.1.19. This will
display the login screen to log the web server that will allow further configuration - sign up
to the administrator account, p. 5.6.3.2. After logging in to the monitor web server it is
possible to change the network parameters according to our needs - especially the IP
address must be changed to make sure that the monitor does not have the default IP
address, otherwise the configuration of other monitors working in the same Ethernet
network will be difficult.

5.4. Functions of the monitor

Monitor PCE-HT 422 performs the following functions:

• measurement of the ambient temperature and relative humidity,

• measurement of luminous,

• measurement of the total amount of volatile organic compounds,

• measurement of CO2 concentration,

• calculation of selected physical quantities: absolute humidity, dew point

temperature, wet bulb temperature, saturated vapor pressure, enthalpy

• memory of minimum and maximum values measured and calculated:

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◦ temperature,

◦ relative humidity,

◦ absolute humidity,

◦ dew point.

Table 1, 2 shows the symbols displayed on the LCD, and their meanings.

Table 1

Symbol Display mode Meaning

constant file system internal memory installed and ready

for operation

flashing error of file system internal memory

flashing file system internal memory full

5.5. Description of PCE-HT 422 monitor reading field

Fig. 5 Description of the PCE-HT 422 monitor reading field

The PCE-HT 422 monitor is equipped with a backlit LCD display consisting of two
lines of 16 characters each. The top line of the display is used for the presentation of
measured values - temperature and relative humidity and to display status pictographs
of the file system internal memory. The bottom line of the display shows the internal
memory usage, status of alarms, time and date. The display (top line) cyclically
changes the displayed parameters. The change interval and displayed parameters are
configurable items.

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flashing file system internal memory installed and ready

for operation, active FTP connection

constant Alarm activity indicator - alarms 1, 2 active

constant Alarm activity indicator - alarm 1 active

constant Alarm activity indicator - alarm 2 active

constant Alarm activity indicator - alarms inactive

Table 2

Symbol

Percentage of internal

memory usage

87.5…100%

75…87.5%

62.5…75%

50…62.5%

37.5…50%

25…37.5%

12.5…25%

0…12.5%

Measuring ranges exceedings are indicated by displaying special characters on the top
line of the LCD:

● - lower exceeding of the range of the displayed value

● - upper exceeding of the range of the displayed value

5.6. Ethernet 10/100-BASE-T

PCE-HT 422 monitors are equipped with Ethernet interface for the connection
(using RJ45 slot) to a local or global network (LAN or WAN) and the use of network
services implemented in the monitors: Web server, FTP server, Modbus Slave TCP/IP,
SMTP client. In order to use the network services Ethernet parameters of the
monitor must be configured. Standard Ethernet parameters of the monitor are shown in
table 4. The basic parameter is the IP address of the monitor - by default

192.168.1.19, which must be unique within the network to which we connect the
device. The IP address can be assigned to the monitor automatically by DHCP
server present on the network provided that the option to acquire IP address from
DHCP servers is enabled in the monitor.

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DHCP service is disabled by default, then the monitor initializes with the default IP address
allowing the user to change the IP address through the website.

Caution: The monitor allows for up to 10 connections simultaneously!! The applications
implemented in the monitor use from 1 to 2 connections:

● Modbus TCP/IP - 1 connection

● Web server - minimum 1 connection

● FTP server - 2 connections

● SMTP client - 1 connection

5.6.1. Connection of 10/100 BASE-T interface

To access the Ethernet services, it is required to connect the monitor to the network
via the RJ45 slot located at the top of the monitor, operating in accordance with TCP/IP.

Fig. 6 View and numbering of RJ45 slot pins

Description of the monitor RJ45 slot diodes function:

● U/FTP – twisted pair cable with each pair foiled,

● F/FTP – twisted pair cable with each pair foiled, additionally cable with foil shield,

● S/FTP (formerly SFTP) – twisted pair cable with each pair foiled, additionally cable

with wire mesh shield,

● yellow LED - illuminates when PCE-HT 422 is properly connected to the Ethernet
network
100 Base-T, does not light up when PCE-HT 422 is not connected to the network
or is connected to 10-Base-T network.

● green LED - Tx/Rx flickers when the monitor sends and receives data, illuminates
constantly when data is transmitted

In order to connect PCE-HT 422 to the network the user should use twisted pair cable.

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● SF/FTP (formerly S-STP) – twisted pair cable with each pair foiled, additionally with
foil and wire mesh shield,

Categories of twisted pair cable according to the European standard EN 50173

minimum: Class D (category 5) - for high-speed local area networks, includes applications
using the frequency band up to 100 MHz. The description of the connection is shown in
table 3. For Ethernet interface the User should use twisted pair cable of STP type
(shielded) category 5 with RJ-45 connector with conductors colors (in accordance with the
colors described in table 3) acc. to the following standard:

Table 3

Conductor

no.

Signal Conductor color acc. to standard

EIA/TIA 568A EIA/TIA 568B

1 TX+ white-green white-orange

2 TX- green orange

3 RX+ white-orange white-green

4 EPWR+ blue blue

5 EPWR+ white-blue white-blue

6 RX- orange green

7 EPWR- white-brown white-brown

8 EPWR- brown brown

5.6.2. Ethernet interface default parameters

Table 4

No. Name Default value

1. DHCP Enabled or disabled

(cycled when default parameters restoration is forced)

2. IP Address 192.168.1.19

3. Subnet mask 255.255.255.0

4. Default 192.168.1.1

5. DNS 8.8.8.8

● EIA/TIA 568A for both connectors at the so-called simple connection of PCE-HT
422 to the network hub or switch,

● EIA/TIA 568A for the first connector and EIA/TIA 568B for the second connector at
the so-called patch cord connection (crossover) used, among others, when
connecting PCE-HT 422 to a computer.

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5.6.2.1. Changing the parameters of Ethernet interface

Changing the parameters of the Ethernet interface is possible through the built-in

web server.

Fig. 7. View of the window to change the parameters of the Ethernet interface

● obtain device information (serial number, execution code, firmware version,
bootloader version, variant (standard or special),

● preview the current measured values,

● read the status of the device,

● select the language for the Web page,

● perform configuration of most parameters.

5.6.3 Web Server

PCE-HT 422 monitor provides its own Web server that allows remote

monitoring of measured values and remote configuration and readout of the monitor
status. With the web page the user can:

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Access to the Web server is achieved by entering the monitor IP address in the web

browser, e.g .: http://192.168.1.19 (where 192.168.1.19 is the monitor address).
The standard port for web server is port "80". Server port may be changed by the user.

Caution: For proper web page operation a browser with JavaScript enabled and
compatible with XHTML 1.0 is required (all popular browsers, Internet Explorer, version 8
minimum).

5.6.3.1 General view

Fig. 8. General view of the main website

The function of each tile of the website:

1) The view of measurements and after clicking on the tile displaying graphs with
trends.

2) Ethernet interface settings.

PCE-HT 42x

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3) Archive settings and information about memory usage and the process of data
dump to the file system memory.

4) Alarm settings and information about their status.

5) Information about the device, giving an individual name to the monitor.

6) Setting the time, LCD display and configuration of our displayed values - the groups
of 12 values of any registers of the monitor registers to which we can assign our
own name and display them as a separate tile on the website. Defined records can
be archived and control the alarms.

7) Email configuration.

8) Logging off, return to the login page.

9) Configurable device name

10) Changing the language

11) Time to log off during inactivity

Fig. 9. View of the window to configure the group of our own registers

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Fig. 10. View of a tile displaying a group of our 12 values

5.6.3.2. Selection of Web server user

The monitor has two user accounts for the Web server secured by individual

passwords:

● user: ”admin”, password: ”admin” - access to configuration and the preview of
parameters

● user: ”user”, password: ”pass” - access to the preview of parameters only.

● user: "guest" - access to the preview of the measured values on the home page

only, log on to the guest account does not require entering a user name or
password, it is enough to select "Login as a guest” and then click on "Login"

Fig. 11. View of the login window to the website

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Fig. 12. View of the message window informing that parameters has been

correctly recorded in the device

Fig. 13. View of the message window informing about incorrect data

of the web form

Calling the monitor IP address in the browser, for example http://192.168.1.19

will display the start window in the browser where the user must enter the name
and password. Additionally, you can log in to the "guest” account when you select “Login
as a guest” on the login page. "Guest” user account is
limited to view the measured values on the main page. Log off occurs after 5 minutes
of inactivity.

5.6.3.3. Messages to the user

The web server is equipped with a system of messages to the user. If the user tries

to save the settings into the monitor, a message is returned on the status of
such operation. For mobile applications there is a user notification system built-in
the web browser.

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Fig. 14. View of the message window informing about lack of permission

to view the website content.

Fig. 15. View of the window of the file manager on the web server

In order to download the file, click the file icon, and to delete a file, click the trash

can symbol next to the file icon.

5.6.3.4. Access to the archive file through the web server

PCE-HT 422 allows for access to archive files through the file manager

implemented on the web server that allows the user to retrieve and delete individual
files. To start the archive file manager, click on the tile Archive, and then click the
button Browse arch. Files.

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5.6.3.5 Logic alarms

Fig. 16. View of alarms configuration window

PCE-HT 422 is equipped with 2 logic alarm outputs. Each alarm can operate in one

of six modes. Fig. 17 shows the operation of alarm in the following modes: n-on, n-off, on,
off. The other two modes: h-on and h-off mean respectively, always On and always
Off. These modes are designed for manual simulation of alarm states.

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AL_L - Lower threshold of the alarm
AL_H - Upper threshold of the alarm

Fig. 17. Types of alarms: a) n-on; b) n-off; c) on; d) off.

Caution: In the case of alarm types n-on, n- off, on, off entering AL_L > AL_H will disable
the alarm.

In the "alarm output" tab the user can decide what action will be performed following the
change of the alarm state:

- Buzzer – audible alarm

- E-mail address 1 – sending an e-mail to the recipient No. 1

- E-mail address 2 – sending an e-mail to the recipient No. 2

It is possible to simultaneously select several options at once.

Note: If the user selects the audible alarm for alarm number 1 (2), the same option should
not be selected for alarm 2 (1) !!!

5.6.4 FTP Server

FTP file sharing protocol is implemented in PCE-HT 422 monitors. The monitor

acts as a server, allowing clients to access the internal memory of the meter file system.
Access to files is possible using a computer, tablet with installed FTP
client or another device acting as FTP client. To transfer files using FTP the following
ports are normally used: "1025" - data port and "21" - command port. If necessary, the
user can change the port used by the FTP. Please note, that the configuration of the
server and FTP client ports must be the same.

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FTP client program should work in passive mode, then the connection is

established fully by the client (the client chooses the data port). For file transfer with the
monitor it is possible to use maximum one connection at the same time, that is why the
maximum number of connections must be limited to "1” in the client program.

Fig. 18. View of FTP ports configuration window

5.6.4.1 Selection of FTP user

The monitor has two user accounts for the FTP server secured by individual

passwords:

• user: ”admin”, password: “admin” - access to files saving and reading

• user: ”user”, password: ”passftp” - access to archive files reading only.

FTP user names can not be changed, however it is possible to change the

password for each user - it is recommended to change passwords for security reasons.
The password must contain a minimum of 4 characters. Password change is only possible
through the web page in "Ethernet” parameters group. Passwords can have a maximum of
8 characters. If the password is lost - making it impossible to use the FTP, the factory
defaults of the Ethernet interface must be restored through the Web site, or all settings can
be restored to the factory defaults using the "Reset" button point 4.2. All standard
parameters of the monitor including the Ethernet parameters and password for FTP server
users will be restored:

user ”admin” → password: ”admin” ;

user ”user” → password ”passftp”.

FileZilla can be used as the FTP client. By typing the monitor IP address in the address
field we can view and download archive files.

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5.6.5 E-mail service

Caution:

SMTP proxy server must support AUTH PLAIN
authentication for unencrypted connection.

The service allows the user to send information about alarm events and information in the
form of regular short e-mail messages that contain the following information:

• The time at which the event occurred,

• The quantity that caused the event,

• The measured values which occurred at the moment of alarm status change,

• The name of the device from which the information was sent.

PCE-HT 422 monitors have been equipped with a function to send email

messages using SMTP. To send a message the user must provide authentication data to

SMTP proxy server. The server should be located in the same network as the device.

PCE-HT 422 monitor has a memory buffer allowing for storage of maximum of 20 e-

mail messages. If an e-mail can not be sent on a regular basis, for example, due to
lack of connection they are queued up one after the other until their number does not
exceed 20. When the limit is exceeded, the subsequent messages will be lost. In
the case of transmission errors, wrong configuration or other factors beyond the control
of the device (e.g. Anti-spam protection of SMPT server), the messages may not reach
the recipient.

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1) SMTP server address, for example, "smtp.wp.pl"

2) Address of the sender, .eg. "[e-mail]"

3) Username registered on the SMTP server

4) The password for the specified account on the SMTP server

5) The name of the first recipient to which the message is to be delivered

6) The name of the second recipient

7) The period of sending regular messages

Fig. 19. View of e-mail configuration window

The correct SMTP server port must be configured at "Ethernet" tile in "SMTP” tab.

For unencrypted connections usually ports 25 or 587 are used.

Fig. 20. View of SMTP port configuration window on "Ethernet” tile

To verify the configuration of e-mail, click on the "Send a test message" button on

"E-mail" tile and then, in order to determine the configuration errors, watch the messages
appearing in the upper left corner of the website.

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5.6.6 Modbus TCP/IP

Table 5

No Description

Modbus RTU

(RS485)

Modbus TCP/IP

(Ethernet)

Default value

1.

Device address for MODBUS

protocol

 

1

2 Baud rate

 

9600

3 Transmission mode

 

RTU 8N2

4. Port number of Modbus TCP

 

502

5.

Time to close the port of Modbus

TCP/IP service [s]

 

60

6.

The maximum number of

simultaneous connections to

Modbus TCP / IP service

 

2

The device address is the address of the device for Modbus TCP / IP. By setting the

address of the monitor to "255" the monitor will skip the analysis of the address in Modbus
frame (broadcast mode).

Fig. 21 View of Modbus TCP configuration parameters on "Ethernet” tile

The implemented protocol is in accordance with the PI-MBUS-300 Rev G of Modicon
Company.

PCE-HT 422 monitors allow access to internal registers via Ethernet and

Modbus TCP/IP Slave. Modbus protocol functions and structure of the registers are
described in points 5.5.6.1 – 5.5.6.3. In order to set up a connection it is necessary to set
a unique IP address for the monitor and to set the connection parameters listed in table 5.

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● 03 (03h) – readout of registers group.

● 04 (04h) – readout of input registers group.

● 17 (11 h) - identification of slave device.

Table 6

Address range Value type Description

6000-6198 float (32 bits) Value is placed in two successive 16-bit registers. Registers

contain the same data as 32-bit registers of 7500 range.
Registers are read-only. Bytes order (B1,B0,B3,B2)

7000 -7198 float (32 bits) Value is placed in two successive 16-bit registers. Registers

contain the same data as 32-bit registers of 7500 range.
Registers are read-only. Bytes order (B3,B2,B1,B0)

7500-7599 float (32 bits) Value is placed in 32-bit register. Registers are read-only.

5.6.6.1. Description of implemented functions

PCE-HT 422 monitors have the following MODBUS functions:

5.6.6.2. Map of registers

In PCE-HT 422 monitor the data is placed in 16- bit registers. Process variables

and parameters of the monitor are located in the address space of registers in a
manner dependent on the type of the variable. Bits in 16-bit registers are numbered
from the youngest to the oldest (b0 ... b15). 32-Bit registers (4 Bytes) contain floating
point numbers in IEEE-754 standard. Order of bytes: B3 B2 B1 B0 – the oldest byte is
sent first. 16-Bit registers representing 32-bit values in two subsequent registers are
doubled in another address area with the following bytes order: B1 B0 B3 B2 (Tab. 6).

The map of the PCE-HT 422 monitor registers is presented below.

Caution: All given addresses are physical addresses. In some computer programs, logical
addressing is applied, then addresses must be increased by 1.

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5.6.6.3. Read-only registers

32-bit

registers

(2 x 16)

32-bit

registers

(float) Name

Unit

Unit name

7000/6000 7500 T

o

C Measured temperature

7002/6002 7501 RH % Measured relative humidity

7004/6004 7502 DP

o

C Calculated dew point

7006/6006 7503 AH g/m3Calculated absolute humidity

7008/6008 7504

o

C Temperature of wet-bulb thermometer

7010/6010 7505 hPA Saturated vapor pressure

7012/6012 7506 Enthalpy

7014/6014 7507 Reserved

7016/6016 7508 Reserved

7018/6018 7509 Reserved

7020/6020 7510 min T

o

C Minimum temperature

7022/6022 7511 max T

o

C Maximum temperature

7024/6024 7512 min RH % Minimum relative humidity

7026/6026 7513 max RH % Maximum relative humidity

7028/7028 7514 min DP

o

C Minimum dew point

7030/6030 7515 max DP

o

C Maximum dew point

7032/6032 7516 min AH g/m3Minimum absolute humidity

7034/6034 7517 max AH g/m3Maximum absolute humidity

7036/6036 7518 Device ID

7038/6038 7519 Status

7040/6040 7520 % of internal archive usage

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7042/6042 7521 Reserved

7044/6044 7522 Progress of internal archive rewriting To the file

system

7046/6046 7523 Current time - Current time

7048/6048 7524

Month, day

MMDD

Current date - month, day

7050/6050 7525 Date - year

YYYY

Current date - year

7052/6052 7526 Reserved

7054/6054 7527 the amount of file system memory free space

(kB), value ”-1” means a memory error

7056/6056 7528 Total storage capacity of file system memory

(kB), value ”-1” means no properly installed
memory

7058/6058

...7072/6072

7529-

7536

Reserved

7074/6074 7537 The first defined register displayed

7076/6076 7538 The second defined register displayed

7078/6078 7539 The third defined register displayed

... …. ……….

7096/6096 7548 The twelfth defined register displayed

7098/6098 7549 E lux Illuminance

7100/6100 7550 Reserved

7102/6102 7551 TVOC ppb Total amount of volatile organic compounds

7104/6104 7552 eCO2 ppm CO2 concentration

5.6.7 MQTT Protocol

The PCE-HT 422 recorder has a built-in MQTT client, enabling the

export of measurement data to a master system based on the MQTT protocol.
Communication configuration requires setting the correct address of the MQTT server
(broker), the port on which the server is listening, the name of the device under which the
PCE-HT 422 recorder is to be visible in the parent system, and the name (topic)
under which the data from the recorder will be published. It is also possible to
specify at what time interval the data should be published. MQTT configuration is
available from the e-Con program level, available free of charge from the
manufacturer's website (https://www.pce-instruments.com/english/download-win_4.htm) .

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Fig. 22 View of the MQTT parameter configuration window

Fig. 23. View of the program to upgrade the firmware.

5.7. Firmware upgrade

PCE-HT 422-CLIENT

PCE-HT 422-DATA

PCE -HT 422 monitors implements a feature that allows the user

to upgrade the software using a PC. Free eCon software and update

files are available on the https://www.pce-instruments.com/english/download-

win_4.htm. RS-485 to USB converter connected to a computer is needed to

perform the upgrade, e.g.: PCE-PD10 converter.

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Caution! After upgrading the software, set up the factory setting of
the monitor.

Caution: Software upgrade is only possible when the monitor is directly
connected to PC (no other Master devices connected to RS-485).

Caution: Turning off the power during the software upgrade may result in
permanent damage to the monitor!

5.8. Measured values archiving

5.8.1. The monitor memory structure

Prior to the upgrade, remove the housing of the device and connect the RS-485

conductors to the connector marked "BA"

After starting the eCon program the speed, mode, the monitor IP address and

RS-485 port must be set in the Communication tab. Then click the icon. Connect.
Then click the link Upgrade firmware which will display the window of UPDATER – Fig.

23. Click the Connect button Messages information window contains info about the
progress of the upgrade process. When the port is properly opened the display shows:
Port opened. Switching to the upgrade mode is performed remotely via UPDATER (based
on the settings in eCon or the website - address, mode, speed, COM port) - upgrade
according to the recommended communication parameters, i.e. speed 115200 kb/s, 8N2
mode. If the monitor establishes communication with UPDATER the following
message is displayed in UPDATER program Device found: PCE-HT 422 and the version
of the main program and the bootloader of the connected device, and the monitor display
will show the message "Device is ready." Then, while pressing the button „ ... ” load the file
with the new version of the software in UPDATER. When the file is properly opened,
UPDATER program displays information File opened. Press the Send button. During
upgrade, the percentage update progress is displayed on the bottom row of the
display. After successful upgrade the monitor switches to normal operation, and the
information window shows Done and the upgrade duration.

The current software version can also be checked by reading the greeting messages of
the monitor displayed after powering up.

PCE-HT 422 monitors are normally equipped with 4MB of internal memory for

storing the the current data recorded by the monitor. The monitor can record any
parameter of the 4 measured values - temperature, relative humidity, dew point and
absolute humidity. Additionally, the user can archive each of 12 defined displayed
quantities. Internal memory of the monitor allows for storage of 534336 records. If you
save by default 50% of

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Minimum archiving period is 10 seconds.

Ar_L - Lower threshold of archiving

Ar_H - Upper threshold of archiving

the internal memory (or other value defined by the user), the archive is automatically
rewritten to the file system's memory. The memory is a circular buffer. After the memory is
full, the oldest data is overwritten. The internal archive can be read, copied and deleted.

PCE-HT 422 monitors have file system internal memory of the size of 8GB

(memory size of the file system can be increased on request or according to the
needs of the manufacturer) to which the data from the internal memory are automatically
rewritten in the form of files. Data can be downloaded via Ethernet using FTP or Web site.

5.8.2. Configuration of archiving

Website is used to configure the archiving parameters. Archiving can be continuous

and conditional. Triggering conditional archiving can be carried out in one of
four possibilities presented in Fig. 23 ( n-on, n-off, off, on). Continuous archiving is
activated by selecting h-on archiving type, and it is turned off by selecting the h-off option.

Fig. 23. Types of conditional archiving

5.8.3. File system internal memory

PCE-HT 422 monitors are equipped with file system internal memory. FAT and

FAT32 file systems are supported. During registration the monitor creates directories and
files of the file system in the internal memory. An example of the directory structure is
shown in Fig. 24.

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Apart from the ARCH directory, in which the archived data is placed, SYSTEM

directory is also created on the card where the following files are located:

- start.txt - date and time of the file system internal memory installation (when the monitor
is restarted after power failure)

- manual.pdf - current user’s manual

- enarch.gif – graphic file with info about alarms / archiving configuration

Fig. 24. Directories structure in the memory.

Caution: If these files are deleted, some elements of the website - hints, instructions, may
not be displayed; these files can be removed after logging in FTP server to administrator
account.

Data in the memory is stored in files located in the directories with names

corresponding to the device name and the serial number - see Fig. 24. Whereas the
names of the files correspond to the date of recording and they have the following format
XXXX_YY.Dzz, where XXXX → year , YY → month. The format of the archive file
extension is Dzz, where "zz" is the subsequent number of the archive file from a given
month. For example, the first file in the archive in the month of May 2016 will be
2016_05.D00, the next file: 2016_05.D00 etc. Max. 32 files can be created for a given
month (*.D00 … *.D31). The file is changed automatically when the file size reaches
29 MB.

5.8.4. Structure of archive files

Files containing archived data in the internal memory of the file system are

structured as columns, where successive columns of data are separated from each other
by a tab character. The first line of the file contains the columns header. Data records are
sequentially arranged in rows and the fields of the record are separated from each other
by a tab character. View a sample archive file with archiving further 12 displayed values of

the user is shown in Fig 25.

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Fig. 26. Sample data file

Subsequent fields included in the row describing the record have the following meaning:

● date – the date of the data registration, the date separator character is "-"

● time – hour, minute, second of the recorded data, time separator character is ” : ”

● T, RH, DP, AH, name1, user reg , …. – name of the value to be archived, the default

decimal separator character is ” . ” however, the separator can be changed to ” , ” by
selecting the proper option in the Archive window of the website.

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– range of relative humidity (RH) measurement: 0...95 % without condensation

– intrinsic error of humidity processing: ±3% of the range for RH = 10...90%

±5% in the remaining range

– range of measurement of illuminance 0...60000 lux

resolution 1 lux

– TVOC measuring range 0...60000 ppb

resolution:

0...2008 ppb - 1 ppb

2008...11110 ppb - 6 ppb

11110...60000 ppb - 32 ppb

– measuring range for CO2 concentration 400...60000 ppm

resolution :

400...1479 ppm - 1 ppm

1479...5144 ppm - 3 ppm

5144...17597 ppm - 9 ppm

17597...60000 ppm - 31 ppm

– hysteresis of humidity measurement: ± 1% RH

– basic range of temperature measurement (T): – 20...60 °C

– intrinsic error of temperature processing: ±0.6o C within the range 10...40o C

±1.0o C in the remaining range

– calculated quantities: absolute humidity (a) [g/m3]

dew point temperature (Td) [°C]

Ethernet Interface: 10/100-Base-T

– max. number of simultaneous connections 10

6. Technical data

Basic parameters:

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- protocol: MODBUS RTU

- device address: 1...247

- baud rate: 4800, 9600, 19200,
38400, 57600, 115200,
230400, 256000 bit/s

- transmission mode: 8N2, 8E1, 8O1, 8N1

- maximal time to start the response: 500 ms

Nominal operating conditions:

– power supply: 6 V d.c.

or PoE IEEE 802.3af

– power consumption: < 2 VA

– ambient temperature: – 20...23…60 °C

– air relative humidity: < 95%

[1]

– time of initial warm-up: 15 minutes

– degree of protection provided by housing: IP 20

– mounting: on a wall

– weight <0.3 kg

– dimensions: (120 x 80 x 25) mm

– operating position: with sensor at the bottom

Electromagnetic compatibility

– - immunity to electromagnetic interference acc. to EN 61000-6-2

– - emission of electromagnetic disturbances acc. to EN 61000-6-4

Safety requirements according to EN 61010-1 standard

– installation category III

– degree of pollution 2

– operating voltage relative to earth 50V

– altitude < 2000m

Interface RS-485:

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Parameters of DC power supply unit (option):

– voltage 6 V d.c. ± 5%

– maximum power 6W

[2]

– input voltage 90...253 V a.c.

– operating temperature 0...40 o C

[2]

– dimensions 63.6 x 29.5 x 45.6 mm

[2]

– cable length 1.4 m ± 10%

[2]

– plug ɸ5.5 / 2.1 mm

[1] air humidity without condensation
[2] power supply parameters can be changed

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Table 8

Humidity and temperature monitor

X X XXXXXX X X

Power supply*:

6 V d.c.

1

6 V d.c. , PoE IEEE 802.3af

2

Accessories:

none

0

6 V d.c. power supply unit

1

Version:

0.0.0.0.0.0

Standard

XXXXXX

Special

Language:

Polish/English M
other** X

Acceptance tests:

without additional requirements 0
with quality inspection certificate 1
acc. to customer requirements X

Coding example:

7. Ordering code

PCE-HT 422

* - Monitors of PCE-HT 422 1XXXXXXXXX version require external supply voltage 6
V DC. Monitors of PCE-HT 422 2XXXXXXXXX version can be supplied both from
Ethernet interface through PoE (Power over Ethernet), and from external power supply 6 V
DC.

** - after agreeing with the manufacturer

PCE-HT 422 21000000M1 means a monitor supplied through PoE IEEE 802.3af and 6 V
DC with 6V DC power supply included in the set in the standard version in the Polish
and English language version with the Quality Inspection certificate.