HYDROLOGICAL SERVICES ML1-420 User manual

Hydrological Services Pty Ltd
1
MiniLog
Digital + 4-20mA + BattV + TempC Data Logger
Model : ML1-420
Operation Manual
HYDROLOGICAL SERVICES Pty Ltd
48-50 Scrivener Street
Liverpool NSW 2170
Australia
Ph. 61 2 9601 2022 Fax. [phone]
E-Mail: [e-mail]

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-2 Issue 1.00 6 Apr, 2011
TABLE OF CONTENTS
1.Introduction ......................................................................................................... 3
2.Product Overview................................................................................................ 4
2.1Overview............................................................................................................... 4
3.Installation............................................................................................................ 4
3.1Hardware Connections ....................................................................................... 5
3.1.1Contact Closure input......................................................................................... 6
3.1.2External Power Supply ....................................................................................... 6
3.1.34-20mA Transducer Input.................................................................................. 7
3.1.4Communications.................................................................................................. 7
3.2Setup and Configuring the Logger .................................................................... 9
3.2.1Site Information................................................................................................... 9
3.2.2System Time/Date................................................................................................ 9
3.2.3Sensor + Parameters............................................................................................ 9
3.2.4Communications.................................................................................................. 10
4.Operation.............................................................................................................. 11
4.1Commands / Syntax............................................................................................. 11
4.1.1On-line Help (?) ................................................................................................... 11
4.1.2Communications (BAUD, EV, RE, CLEAR).................................................... 12
4.1.3Battery Voltage (BV, BVINT) ............................................................................ 13
4.1.4Temperature (TEMPC) ...................................................................................... 13
4.1.5Digital Channel Parameters (CHID, INC, TDAY, TOT, TYPED, UD)......... 14
4.1.64-20mA Channel Parameters (CHIDRV, RVHR, TXI, …..U420, WL)......... 15
4.1.7Date/Time Parameters (D, FMT, T, TA)........................................................... 17
4.1.8Dump Log Records (DUR, DURV, ….DUALL, CLR, CLRV, MW, LOG) .. 18
4.1.9Miscellaneous (ID, SI, PASSWD, BYE, SLEEP, RESET, VER).................... 21
4.1.10 Status Window (ST)............................................................................................... 22
4.2Data Output Format............................................................................................ 24
4.2.1Dump Log Record ............................................................................................... 24
5.Specification......................................................................................................... 27
5.1Hardware Specification....................................................................................... 27
5.2LED Indicator...................................................................................................... 28
5.3External Contact Interface................................................................................. 28
5.44-20mA Interface................................................................................................. 28
5.5Communications Interface.................................................................................. 28
5.6Watchdog.............................................................................................................. 28
6.Fault Finding........................................................................................................ 30
Appendix A. Interfacing to a Modem.................................................................................. 32
Appendix B. Installing a RainTrak System ........................................................................ 35
Appendix C. Surge Protection.............................................................................................. 37

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-3 Issue 1.00 6 Apr, 2011
1. Introduction
The Hydrological Services MiniLog Data Logger ML1-420 has been designed using surface
mount technology to provide a very small, ultra low power and reliable data logger that can
be used in harsh environments for extended periods. Flash memory technology has not only
been used for data storage but also for program storage - which provides secure non-volatile
data storage as well as the unique capability of software download as new software features
and revisions become available. The logger can be connected to a standard Tipping Bucket
Rain Gauge OR any device that requires a contact closure to be monitored – it monitors the 4-
20mA signal from a water level transducer, an external 12V battery, the internal battery and
the ambient temperature inside the MiniLog enclosure. The communication features allow for
very flexible operation directly connected to a computer. The unique on-board help feature
allows the user to obtain a list of commands with syntax. The ultra low power allows the
logger to be powered from an internal 3.6V AA lithium battery for 2 years or a 1.5V AA
alkaline battery for 1 year. The indicator LED flashing once a second as a heartbeat, gives the
user confidence that the MiniLog is alive and well.
LAN / WAN
PORTABLE PC
OR
ML1-420
Logger
Logger returnedUnload at site
PC
TBRG
(If applicable)
OR
Communication
Interface
PSTN, GSM, Satellite
River Height
4-20mA Sensor

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-4 Issue 1.00 6 Apr, 2011
2. Product Overview
2.1 Overview
The Hydrological Services MiniLog Data Logger is easily installed within many products due
to its small size. Its primary purpose is to count contact closures and measure and log data
from a 4-20mA sensor / transducer.
One such application would be inside a Tipping Bucket Rain Gauge, (TBRG). Rain falling
on the collecting funnel is directed through a syphon control unit and discharges as a steady
stream into a 2 compartment bucket mounted in unstable equilibrium. As each compartment
fills, the bucket tilts alternately about its axis. Each tip forces a contact closure of a magnetic
reed switch corresponding to a height of rainfall depending on bucket capacity, (Bucket
Capacity can be 0.2 mm, 0.5 mm, 1.0 mm, 0.01 inch). The logger unit accepts the contact
closure and records the event as a time stamp to one second resolution. Each event is stored
in secure, non-volatile flash memory.
At the same time the logger can measure water level using a 4-20mA pressure transducer.
The logger switches the external 12V battery voltage to the 4-20mA loop, and waits the
required warmup period, takes a measurement of the 4-20mA current, turns off the loop
power, scales the result and saves each measurement in secure, non-volatile flash memory in
preparation for data extraction.
The data extraction process is accomplished via a PC or similar. A simple one-to-one DB9
cable connection is made between the PC and logger to allow data retrieval upon operator
command. The data format of the logger file is specified within this document.

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-5 Issue 1.00 6 Apr, 2011
3. Installation
The MiniLog has a single DB9 female connector, which is mainly used for communications –
(the digital input and external power may be taken through this connector, making it pin
compatible with the ML1). The pinout is designed to be compatible with direct connection to
a PC Comm port. Note that when external power is supplied, whether though an external 12V
battery or RS232 handshake lines, the power drawn from the internal battery is reduced to
zero.
The digital input from the TBRG, external 12V power and the 4-20mA transducer are
connected to the internal screwless terminal blocks – these specific terminals are used
because they keep a constant tension on the wires that are inserted.
1. Use a small flat blade
screwdriver and push-
down on the oran
g
e
2. Insert the stripped
wire here.
3. Release the orange
lever to secure the wire.
4. Pull on the wire to
make sure it is secure.
TBRG
12V
Battery
WL3100
AD375MA
ML1-420
4-20mA
“OR”
Submersible
4-20mA
Pressure
Transducer
Model: PS98i
“ML1-420 Typical Application”
Rainfall
Water Level

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-6 Issue 1.00 6 Apr, 2011
3.1 Hardware Connections
3.1.1 Contact Closure input
The voltage free contact to be monitored should be connected either between Pin 9 (contact
closure input) and Pin 5 (Gnd) with PCB solder link LK1 bridged OR it can be connected
to the internal screwless terminal block, through a cable gland on the enclosure. (Note that
the PCB solder link LK1 is an option that is left open circuit when the ML1-420 is supplied
from the factory.) (Also Note: In the first option (shown on the left), an extra tip will be
generated when the DB9 connector is plugged into a PC, unless pin 9 is clipped on the DB9
lead.)
Connection of Contact Closure Input
3.1.2 External Power Supply
While the MiniLog ML1-420 is in the field monitoring a 4-20mA transducer, an external 12V
power source must be connected to provide power to the transducer. The logger switches the
12V to the transducer, and waits for the preset warmup period (as set by the TXI parameter),
and then measures the 4-20mA current that is passing through the sense resistor. The logger
only uses the internal battery for maintaining the time while there is no external power source
present.
The ML1-420 draws power from the RS232 signals for communications when there is no
external power source present. (Note that this is not sufficient to power a 4-20mA
transducer.)
The internal and external voltage is measured and logged periodically by the logger. The
logging interval is set with the “BVINT” command, which can be set from 1 to 999 minutes.
The logged data can be retrieved with the DUBVI (internal battV) command, DUBVE
(external battV) command, DUBVT (battV and tempC) command or the DUALL (dump All)
command.
While the MiniLog ML1-420 is in the field monitoring the contact closure only, an external
power supply is not required. The logger enters a “sleep” mode, waking only to update the
time, and log a contact closure event. In this mode the logger will operate continuously for 2
years on the internal 3.6V lithium battery (or 1 year on a 1.5V alkaline battery).
External
Voltage
Free
Contac
t
9
5
MiniLog
ML1-420 DB9 pins
LK1
Screwless
terminals
Monitor
Circui
t
OR
External
Voltage
Free
Contac
t
9
5
MiniLog
ML1-420 LK1
Screwless
terminals
Monitor
Circui
t

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-7 Issue 1.00 6 Apr, 2011
Internal battery
for maintaining
time when no
external power
is present !
ML420
Sense
Brown
4-20mA
Transducer
Green
4-20mA+
12V Battery
-
+
Batt +12V
Batt 0V
4-20mA-
3.1.3 4-20mA Transducer Input
The 4-20mA connection is via 2 wires into a screwless terminal block. The battery voltage is
switched to the 4-20mA transducer and the current is measured across an internal sense
resistor.
Connection of 4-20mA Transducer
3.1.4 Communications
The pinout of the DB9 female connector on the front of the ML1-420 logger is as follows :-
Pin
Connection ML1-420 Logger Signal Name DB9 Female PC Signal Direction PC Signal DB9 Male
1 No Connection CD
2 Tx (RS232 Serial data output) Rx
3 Rx (RS232 Serial data input) Tx
4 External Power (+ DTR / DSR loop) DTR
5 Gnd Gnd
6 External Power (+ DSR / DTR loop) DSR
7 External Power (+ RTS / CTS loop) RTS
8 External Power (+CTS / RTS loop) CTS
9 Contact closure input (See note 3) RI
Notes:
1. When the ML1-420 is directly connected to a PC the following handshake signals are
linked
Pins 4 and 6 are linked together inside the ML1-420.
Pins 7 and 8 are linked together inside the ML1-420.

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-8 Issue 1.00 6 Apr, 2011
2. When the ML1-420 is directly connected to a PC, sufficient power is extracted from the
handshake signals to power the ML1-420 – which prevents power drain from the internal
battery while communications is in progress.
3. A solder link LK1 on the ML1-420 PCB allows the digital input from the TBRG to be
connected through pin 9 of the DB9F connector. See section 3.1.1 for more details.
The DB9 female connector on the logger is the communications port and is setup as a DCE.
This allows direct connection to a PC comm port using a DB9 male to DB9 female 1-to-1
cable. (The minimum connection is pins 2, 3, 4 and 5.)
Minimum Connection of PC on DB9F
Communications can also be active while the contact closure input on pin 9 is used when
jumper LK1 is soldered, and a special cable is prepared.
Connection of PC together with Contact Closure Input through the DB9F
PC
Comm
Port
1
8
MiniLog
ML1-420
2
3
4
5
6
7
9
DB9
Female
1
8
2
3
4
5
6
7
9
DB9
Male
PC
Comm
Port
1
8
MiniLog
ML1-420
2
3
4
5
6
7
9
DB9
Female
1
8
2
3
4
5
6
7
9
External Voltage
Free Contact
(TBRG)
DB9
Male
Contact
monito
r
LK1
Tx
Rx
DTR
(p
ulled hi
g
h
)
Gn
d

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-9 Issue 1.00 6 Apr, 2011
3.2 Setup and Configuring the Logger
Once the ML1-420 logger has been connected to a computer, the parameters can be setup
using WinComLog or any ‘dumb’ terminal emulation program. (NOTE: If a third party
application is used, the handshake signals DTR and RTS should be forced high to enable the
MinLog to have power.) If using a third party program, it should be set for the appropriate
baud rate, and 8/N/1 (bits/parity/stop), handshake off, and “local echo on”. On receipt of
individual commands from the computer, the logger will respond with the present parameter
setting. (Note that the command keywords permit both upper and lower case characters, or a
combination of both.) A carriage return ( < CR > , Enter Key) immediately following an
entry will action the command. Invalid entries return a “Command Error” response. A list of
all logger commands may be viewed on the computer screen by using the unique on-board
help system. Simply type ? and then press the Enter key.
Data and parameter security is provided by means of a user password. Any data or
parameters may be viewed without a password, but parameters may only be altered and data
may only be cleared after the password has been entered correctly. The default password
when the logger is supplied is “BOMM”. Parameters may be entered by typing the command,
then the equals symbol (=) and then the new parameter, followed by the Enter key.
3.2.1 Site Information
The “Site Information” (SI) is a user definable 16 character string that allows each logger to
have a unique location name. Alternatively, loggers in a locality may be given the same
name and the rainfall channel ID may be used to uniquely identify the logger data. This
allows for easy identification of dumped data or status window information. See section
4.1.8 for more information on this command.
3.2.2 System Time/Date
The “Time” (T) and “Date” (D) should be checked for accuracy during installation.
The “Time Adjust” (TA) command allows the Real Time Clock to be adjusted for crystal
frequency inaccuracies.
3.2.3 Sensor + Parameters
The Minilog ML1-420 has several parameters that allow characterisation of the sensor being
used. The “Channel ID” (CHID) is a 7 digit user definable number that should be set to
uniquely identify the digital (rainfall) channel. The “Increment” (INC) parameter defines the
capacity of the specific digital sensor used as well as the number of external events that
constitute one logged event - this determines the digital input resolution.
The “River Channel ID” (CHIDRV) is a 7 digit user definable number that should be set to
uniquely identify the 4-20mA (river) channel. The “Transducer Range” (TXR) parameter
defines the 4-20mA Range of the transducer. The “Transducer Interval” (TXI) parameter
defines how often a transducer measurement is taken, and how long the transducer is powered
for. The “River Height Ref” (RvHR) parameter defines the offset of the water height.
See section 4.1.4 for more information on these commands.

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-10 Issue 1.00 6 Apr, 2011
3.2.4 Communications
The MiniLog ML1-420 has an RS232 serial interface to support asynchronous ASCII
communications to accommodate data extraction and user set-up. This port operates at 1200,
2400, 4800, 9600, 19200, 38400 and 57600 baud with 8 data bits, no parity and 1 stop bit.
If initially you can’t establish communications with the ML1-420, try each of the 7 baud
rates, in case it has been changed from the default rate of 9600.
Each digital input event, and 4-20mA measurement that is logged is also transmitted on the
serial port, unless the event output flag is off (EV=off).
The RS232 serial port interface may be connected to a modem for remote interrogation and
data retrieval – see Appendix A for more details.

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-11 Issue 1.00 6 Apr, 2011
4. Operation
4.1 Commands / Syntax
The following sections give detailed information on each of the MiniLog ML1-420
commands. Simply type the command and then press enter to view the parameter. To change
a parameter, the password must first be entered, and then type the command followed by =,
then the new parameter followed by Enter. Eg. SI=Sydney then press Enter.
4.1.1 On-line Help (?)
Type a ?then press Enter to get the following help screen. The commands are listed in alphabetical
order. On-line Help
?
ML1-420 Data Logger Command Syntax [...] = optional to set parameter
(Command may be upper and/or lower case) <CR> = press carriage return
======== General Commands ===================================================
BAUD[=xxxx]<CR> (comms BAUD rate) BYE<CR> (exit passwd access)
CLEARx[=30char]<CR> (Clear Seq.x=1,2,3,4) D[=d/m/y OR m/d/y]<CR> (Date)
EV[=On/Off]<CR> (EVent output) FMT[=dmy/mdy]<CR> (date ForMaT)
ID<CR> (logger ID) LOG[=On/Off] (En/Disable Logging)
MW[=On/Off]<CR> (Memory Wrap) PASSWD=****<CR> (4 char password)
RE[=On/Off]<CR> (REsponse output) RESET<CR> (software RESET)
SI[=16chars]<CR> (SIte name) SLEEP[=N]<CR> (Set Sleep time mins)
ST<CR> (STatus window) T[=hh:mm:ss]<CR> (Time)
TA[=hh:mm:ss] (Time Adjust) VER<CR> (s/w VERsion)
======== Battery Voltage and Temperature Commands ===============================
BV<CR> (Batt. Voltages now) BVINT[=mmm] (BV/TempC log INTerval)
TEMPC<CR> (TEMPerature oC now)
======== Digital Input Commands ==============================================
CHID[=7 dig]<CR> (CHannel ID - Digital) INC[=x.x/mm]<CR> (INCrement+mult.)
TDAY<CR> (Total toDAY) TOT<CR> (TOTal)
TYPED[=16chars]<CR> (TYPE of Dig i/p) UD[=8char]<CR> (Units Digital)
======== 4-20mA Input Commands =============================================
CHIDRV[=7 dig]<CR> (CHannel ID – 4-20mA) RVHR[=xxx.xxx]<CR> (RiVer Height Ref)
TXI[=mmm/tt]<CR> (Transducer Interval) TXR[=xxx.xxx]<CR> (Transducer Range)
TYPE4[=16chars]<CR> (TYPE of 4-20 logger) U420[=8char]<CR> (Units 4-20)
WL<CR> (Water Level now)
======== Dump/Clear Commands ===============================================
CLR<CR> (Clear all Records) CLRV<CR> (Clear all Records)
DUR/N/h:m/d/m/y<CR> (DUmp Rain log) DURV/N/h:m/d/m/y<CR> (DUmp RiVer log)
DUBVI[....]<CR> (DUmp BattV.Internal) DUBVE[....]<CR> (DUmp BattV.External)
DUTMP[....]<CR> (DUmp TempC) DUBVT[....]<CR> (DUmp BattV+TempC)
DUALL[....]<CR> (DUmp ALL Data) (All dump commands have the same syntax)
eg. DUR => Dump all Rainfall data
DUR/3 => Dump last 3 days of Rainfall data
DURV/10/12:00/15/2/11 => Dump 10 days of River data from 12:00 15-Feb-11
---------------------------------------------------------------------------------------------------------------------------
Water Level (WL) = (((Measured 4-20mA)-4)/16) x Range (TXR) + Offset (+/-RVHR)

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-12 Issue 1.00 6 Apr, 2011
4.1.2 Communications (BAUD, EV, RE, CLEAR)
The “Baud” (BAUD) command allows the baud rate to be viewed or changed. Acceptable
baud rates are 1200, 2400, 4800, 9600, 19200, 38400 and 57600.
BAUD<CR> Display the present baud rate
BAUD= 9600<CR> Set the baud rate to 9600 baud
The “Event” (EV) flag allows the time stamps that are transmitted on the serial port to be enabled or disabled.
When an event occurs, the time is transmitted on the serial when EV is on. When EV is off, nothing is
transmitted on the serial port when an event occurs.
EV<CR> Display the state of the event flag.
EV=ON<CR> Enable event reporting
EV=OFF<CR> Disable event reporting
The “Response” (RE) flag allows the error response to commands, to be enabled or disabled.
When RE is on then you may see “Command Error” or “Syntax Error” messages appear if the
MiniLog does not understand what was typed. When RE is off then there will be no response
if the MiniLog does not understand what was typed. It is useful to turn this off when
connected to a modem, so that the MiniLog and the modem don’t engage in endless
“Command Error” conversations.
RE<CR> Display the state of the response flag.
RE=ON<CR> Enable all error responses.
RE=OFF<CR> Disable all error responses.
The “Clear” (CLEAR1/2/3/4) command sequences are used to control an external modem –
that is, force it into a known state. (If there is no modem connected to your MiniLog, then
these sequences can be left clear. Eg. Set CLEAR1=<CR> then CLEAR2=<CR> then
CLEAR3=<CR> and finally CLEAR4=<CR>)
The Clear sequences are performed when a Bye command is received, and/or if no comms is
received within the Sleep timer period.
There is a maximum of 30 characters in each of the 4 clear sequences. Special characters
include ~ = 0.5 second pause and ^= CTL character (Eg ^M = carriage return)
The format of each sequence is CLEAR1 = Command Sent / Expected Reply / Timeout

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Data Logger Model ML1-420
© Copyright ML1-420 100-13 Issue 1.00 6 Apr, 2011
Eg CLEAR1=+++~~ATH^M/OK/10 Sends +++, then waits 1 second, then send
ATH<CR> then waits up to 10 seconds for an
OK response.
The expected reply and the timeout parameters are optional. If no timeout is specified, then a
default of 60 seconds is used. The timeout may be a one or two digit number.
CLEAR1<CR> Display the clear1 sequence
CLEAR1=+++~~<CR> Set the clear 1 sequence. Send +++ then wait 1 sec
CLEAR1=+++//5<CR> Send +++, no response and wait 5 seconds
After CLEAR1 sequence is performed, CLEAR2 then CLEAR3 and finally CLEAR4
sequence is performed.
4.1.3 Battery Voltage (BV, BVINT)
The MiniLog battery voltage is measured and displayed when the battery voltage command
(BV) is executed as well as during a status window command (ST)
BV<CR> Displays the internal and external battery voltages
The battery voltage log interval can be set with the (BVINT) command from 1 to 999 mins.
The internal battery, external battery and temperature are logged at this interval. The logged
data can be retrieved using the DUBVI, DUBVE, DUBVT and DUALL commands.
BVINT<CR> Displays the log interval in mins.
BVINT=015<CR> Set the battery and temperature log interval to 15 mins.
4.1.4 Temperature (TEMPC)
The MiniLog tempearture is measured and displayed when the temperature command
(TEMPC) is executed as well as during a status window command (ST)
TEMPC<CR> Displays the internal temperature in degrees C
The temperature log interval is be set with the (BVINT) command above, from 1 to 999
mins. The internal battery, external battery and temperature are logged at this interval. The
logged temperature can be retrieved using the DUTMP, DUBVT and DUALL commands.

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-14 Issue 1.00 6 Apr, 2011
4.1.5 Digital Channel Parameters (CHID, INC, TDAY, TOT, TYPED, UD)
The “Channel ID” (CHID) is a 7 digit user definable number that should be set to uniquely
set to identify the channel.
CHID<CR> Displays the present Digital Channel ID
CHID=0012345<CR> Sets the Digital Channel ID to 0012345
The “Increment” (INC) is a parameter that specifies the quantity that each contact closure
represents. This might be 0.2mm of rain for a tipping bucket rain gauge, or 10 litres of water
for a flow meter, or 1 widget for a product counter. The parameter is split into 2 parts – the
first part is the amount that each contact closure represents, and the second part is the number
of contact closures that represent one event. The increment command has 5 different
acceptable formats.
INC<CR> Display the existing increment parameter.
INC=0.01/01<CR> Defines say a TBRG bucket of 0.01 inches of water, and one tip
represents one logged event.
INC=0.2/01<CR> Defines say a TBRG bucket of 0.2 mm of water, and one tip
represents one logged event.
INC=10/10<CR> Defines say 10 litres of water per contact closure of a flow
meter, and 10 such closures logged as one event. This means
that each event represents100 litres of water.
INC=100/01<CR> Defines say 100 litres of water per contact closure of a flow
meter, and 1 such closure logged as one event.
INC=1000/05<CR> Defines say 1000 washers in a box, and 5 such boxes logged as
one event. This means that each event represents 5000 washers.
The “Total” (TOT) command allows the Total number, of whatever is being counted, to be
displayed. This is the total since the last reset – or the total since the last CLR record clear.
TOT<CR> Displays the total of what is being counted since the last record
clear.
The “Total Today” (TDAY) command allows the Total number, of whatever is being
counted, to be displayed. This is the total today since midnight.
TDAY<CR> Displays the total of what is being counted since midnight.

Hydrological Services Pty Ltd
Data Logger Model ML1-420
© Copyright ML1-420 100-15 Issue 1.00 6 Apr, 2011
The “Type Digital” (TYPED) is a 16 character user defined string that allows the Status
Window to be customised for your counting application. It simply changes the aesthetics of
the Status Window. The MiniLog may be used for accumulating Rainfall, measuring Flow,
counting People or Cars etc…. It is best to start this parameter with a capital letter – for
aesthetic reasons.
TYPED<CR> Display the digital channel Type
TYPED=Rainfall<CR> Set the digital type to Rainfall
TYPED=Flow<CR> Set the digital type to Flow.
The “Units Digital” (UD) is a user defined 8 character string that assists in defining what is
being counted. For example it may be mm or inches or litre/hr or widgets. This parameter is
so the retrieved data has meaning.
UD<CR> Display the present units.
UD=mm<CR> Set the units to mm.
4.1.6 4-20mA Channel Parameters (CHIDRV, RVHR, TXI, …..U420, WL)
(CHIDRV, RVHR, TXI, TXR, TYPE4, U420, WL)
The “Channel ID River” (CHIDRV) is a 7 digit user definable number that should be set to
uniquely set to identify the 4-20mA channel.
CHIDRV<CR> Displays the present 4-20mA Channel ID
CHIDRV=0012345<CR> Sets the 4-20mA Channel ID to 0012345
The “River Height Reference” (RVHR) is a parameter that is an “offset” added to the river
height as measured by the transducer.
RVHR<CR> Display the present River Height Reference.
RVHR=5.000<CR> Sets the offset to 5.000 m
RVHR= –520.000<CR> Sets the offset to –520.000 m
The “Transducer Interval” (TXI) is a parameter that defines the frequency that analog
measurements are made, as well as the time that the transducer is powered before a
measurement is made.
TXI<CR> Displays the present Transducer Interval.
TXI=015/07<CR> Set to measure the transducer every 15 minutes, and leave the

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transducer powered for 7 secs before measuring. Transducer
will be powered at 00:00, 00:15, 00:30, 00:45, 01:00, 01:15,….
The “Transducer Range” (TXR) is a parameter that defines the 20mA transducer depth. Zero
depth is usually represented by 4mA and maximum depth is represented by 20mA. This
parameter is determined by the particular transducer connected to the ML1-420.
TXR<CR> Displays the present Transducer Range.
TXR=10.000<CR> Set the 20mA depth to 10.000m
TXR=1.000<CR> Set the 20mA depth to 1.000m
The “Type 4-20mA” (TYPE4) is a 16 character user defined string that allows the Status
Window to be customised for your measurement application. It simply changes the aesthetics
of the Status Window. The MiniLog may be used for measuring River Level, Dam Level,
etc…. It is best to start this parameter with a capital letter – for aesthetic reasons.
TYPE4<CR> Display the MiniLog Type
TYPE4=River<CR> Set the logger to River
TYPE4=Dam<CR> Set the logger to Dam.
The “Units 4-20mA” (U420) parameter is a user defined 8 character string that assists in
defining what is being measured. For example it may be mm or inches or litre/hr or widgets.
This parameter is so the logged data has meaning.
U420<CR> Display the present units.
U420=m<CR> Set the units to m.
The “Water Level” (WL) command initiates an analog measurement of the 4-20mA
transducer and displays the result to 3 decimal places. The message “Please Wait…” will
appear while the transducer is warming up prior to the actual measurement.
WL<CR>
Please Wait…
12.981
The Water Level value displayed is created as follows :
Water Level (WL) = (((Measured 4-20mA)-4)/16) x Range (TXR) + Offset (RVHR)
The result displayed when a WL command is performed is also logged into memory with the
time.

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4.1.7 Date/Time Parameters (D, FMT, T, TA)
The MiniLog date and time is maintained by the microprocessor, and the LED flashing once a
second indicates that the logger is alive and operational. (This flash is only 1mS in duration
and consequently the power consumption is negligible.)
The “Date” (D) is displayed as day/month/year or month/day/year with slash separators. (This
depends upon the format (FMT ) parameter.)
D<CR> Displays the date.
D=22/09/05<CR> Set the date. (Note: leading zeros are optional, BUT
D=9/3/5<CR> day+month+year must be entered)
The “Format”(FMT) parameter is used to change the date format to either day/month/year or
month/day/year.
FMT<CR> Display the present format as “dmy” or “mdy”
FMT=dmy<CR> Set the date format to day/month/year.
FMT=mdy<CR> Set the date format to month/day/year
The “Time” (T) is displayed in 24 hour format separated by colons. When entering the time
and date, all fields must be entered. Note that if the time is entered as T= then it will be reset
to midnight 00:00:00.
T<CR> Displays the time in 24 hour format
T=9:45:00<CR> Set the time (Note: leading zeros are optional BUT
T=16:7:0<CR> hrs+mins+secs must be entered)
The “Time Adjust” (TA) command performs the same function as the time (T) command,
except it determines if the clock is running fast or slow, and calculates an adjustment to add
or subtract 1 second every xxx hours. In effect, this is a software adjustment to bring the
clock into specification. A sample procedure would be :
1. Set the time accurately using the T=12:35:00<CR> command
2. Wait at least 12 hours (the longer the time period the better the accuracy –
this could be over many months.)
3. Set the time again using the TA=17:13:30<CR> command

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The new time adjustment will be calculated and displayed. (NOTE: If there is already a time
adjustment in progress, then the MiniLog will take this into account when calculating the new
adjustment.) After this procedure the clock accuracy will be improved considerably.
TA<CR> Display the present time adjustment
eg. +1 Sec every 0014 hours
TA=<CR> Remove the existing time adjustment.
TA=10:13:55<CR> Set the time to 10:13:55 and calculate the new time adjustment.
4.1.8 Dump Log Records (DUR, DURV, ….DUALL, CLR, CLRV, MW, LOG)
(DUR, DURV, DUBVI, DUBVE, DUBVT, DUTMP, DUALL, CLR, CLRV, MW, LOG)
The MiniLog ML1-420 logged data is stored in the on-board flash memory.
The “Dump Rain log” (DUR) command, unloads the historical records from the start of the
record to the most recent event stored. On completion of successful data retrieval, the
memory remains intact until cleared by the clear rain log user command (CLR) – please note
that the CLR command clears all logged data, rain, river, battery and temperature!! When the
memory becomes full, with Memory Wrap off, the logger stops logging and tacks a “Mem
Full” message onto the end of an event message. When Memory Wrap is on, and memory
becomes full, the oldest records are erased and replaced by the newest records. The log is
dumped in ascii format, as shown in section 4.2.1.
DUR<CR> Dump the complete rain log record.
The “DUR” command also allows for searching through the log and starting at a specific
location instead of always dumping the complete log record.
Syntax : DUR / No of days / Time / Date
Examples :
DUR/2<CR> Dump 2 full days of data, starting 2 days back from the current
date at 00:00
DUR/1/1:40<CR> Dump 1 day of data starting at 1:40am today
DUR/30/12:00/1/1/11 Dump 30 days of data starting at 12:00pm on 1-Jan-2011
DUR/12/15:30/13 Dump 12 days of data starting at 3:30pm on the 13th day of the
current month and year. (Note that the date format in this
example is Day/Month/Year)
DUR/L Dump all the data since the last dump
NOTE : The format of the date in the DUR command depends upon the date format in the
MiniLog – that is either Day/Month/Year or Month/Day/Year.

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The “Dump Internal Battery Voltage log” (DUBVI) command, unloads the internal battery
voltage log from the start of the record to the most recent event stored. On completion of
successful data retrieval, the memory remains intact until cleared by the clear log command
(CLR) – please note that the CLR command clears all logged data, rain, river, battery and
temperature!! The log is dumped in ascii format, as shown in section 4.2.1.
DUBVI<CR> Dump the complete internal battery voltage log record.
(The DUBVI command has all the same search syntax as the DUR command.)
The “Dump External Battery Voltage log” (DUBVI) command, unloads the external battery
voltage log from the start of the record to the most recent event stored. On completion of
successful data retrieval, the memory remains intact until cleared by the clear log command
(CLR) – please note that the CLR command clears all logged data, rain, river, battery and
temperature!! The log is dumped in ascii format, as shown in section 4.2.1.
DUBVE<CR> Dump the complete external battery voltage log record.
(The DUBVE command has all the same search syntax as the DUR command.)
The “Dump Battery Voltages and temperature log” (DUBVT) command, unloads the internal
and external battery voltage and temperature log from the start of the record to the most
recent event stored. On completion of successful data retrieval, the memory remains intact
until cleared by the clear log command (CLR) – please note that the CLR command clears all
logged data, rain, river, battery and temperature!! The log is dumped in ascii format, as
shown in section 4.2.1.
DUBVT<CR> Dump the complete internal+external BV + tempC log record.
(The DUBVT command has all the same search syntax as the DUR command.)
The “Dump Temperature log” (DUTMP) command, unloads the temperature log from the
start of the record to the most recent event stored. On completion of successful data retrieval,
the memory remains intact until cleared by the clear log command (CLR) – please note that
the CLR command clears all logged data, rain, river, battery and temperature!! The log is
dumped in ascii format, as shown in section 4.2.1.
DUTMP<CR> Dump the complete temperature log record.
The DUTMP command has all the same search syntax as the DUR command.
The “Dump All log” (DUALL) command, unloads all data from the start of the record to the
most recent event stored. On completion of successful data retrieval, the memory remains
intact until cleared by the clear log command (CLR) – please note that the CLR command
clears all logged data, rain, river, battery and temperature!! The log is dumped in ascii

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format, as shown in section 4.2.1.
DUALL<CR> Dump the complete log of all parameters.
The DUALL command has all the same search syntax as the DUR command.
The “Dump River log” (DURV) command, unloads the 4-20mA river level log from the start
of the record to the most recent event stored. On completion of successful data retrieval, the
memory remains intact until cleared by the clear log command (CLRV) – please note that the
CLRV command also clears all logged data, rain, river, battery and temperature!! The log is
dumped in ascii format, as shown in section 4.2.1.
DURV<CR> Dump the complete 4-20mA River log record.
The DURV command has all the same search syntax ad the DUR command.
The “Memory Wrap” (MW) command, enables or disables the wrapping of memory. When
memory wrap is on, and the historical log becomes full, then the first data stored will be
erased one block at a time. (A block of Flash memory holds approximately 400 events, and
there are 1023 blocks available.) In this mode memory never becomes full, and the most
recent data is always available. It is advisable that when changing the state of the Memory
Wrap flag, the existing logged data be erased so that logging can start afresh.
MW<CR> Display the present state of the memory wrap flag
MW=ON<CR> Turn memory wrap on.
MW=OFF<CR> Turn memory wrap off.
NOTE: It is best to clear all of memory (using CLR) when changing this flag.
The “Clear Record” (CLR) command erases the complete memory log of all history – note
that this command erases the Rain, River, Battery Voltage and Temperature logs. A question
will appear to remind the user that all data will be erased – answer y or Y to delete the log
and any other key to abort.
CLR<CR> Erase complete log record.
*** This will clear the Rain, River, Battery and TempC Logs *** : Are you sure ? (Y/N) Y
The “Clear River Record” (CLRV) command erases the complete memory log of all history
– note that this command erases the Rain, River, Battery Voltage and Temperature logs. A
question will appear to remind the user that all data will be erased – answer y or Y to delete
the log and any other key to abort.
CLR<CR> Erase complete log record.
*** This will clear the Rain, River, Battery and TempC Logs *** : Are you sure ? (Y/N) Y