LTH Electronics MXD70 Series User manual
MXD70 SERIES
Multi-parameter Monitor
Setpoints, Current Outputs,
And Digital Inputs
Configuration Guide
reface
MXD70 Setpoints, Current Outputs,
and Digital Inputs Configuration Guide
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Preface
Product warranty
The MXD70 Series has a warranty against defects in materials and workmanship for three
years from the date of shipment. During this period LTH will, at its own discretion, either
repair or replace products that prove to be defective. The associated software is provided
‘as is’ without warranty.
Limitation of warranty
The foregoing warranty does not cover damage caused by accidental misuse, abuse,
neglect, misapplication or modification.
No warranty of fitness for a particular purpose is offered. The user assumes the entire risk of
using the product. Any liability of LTH is limited exclusively to the replacement of defective
materials or workmanship.
Disclaimer
LTH Electronics Ltd reserves the right to make changes to this manual or the instrument
without notice, as part of our policy of continued developments and improvements.
All care has been taken to ensure accuracy of information contained in this manual.
However, we cannot accept responsibility for any errors or damages resulting from errors
or inaccuracies of information herein.
Copyright and trademarks
All rights reserved. Translations, reprinting or copying by any means of this manual,
complete or in part or in any different form requires our explicit approval.
MXD70 is a trademark of LTH Electronics Ltd
First edition: June 2011
LTH Electronics Ltd
Chaul End Lane
Luton Telephone : +44 (0)1582 593693
Bedfordshire Fax : +44 (0)1582 598036
England Web : www.lth.co.uk
reface
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MXD70 Setpoints, Current Outputs, and
Digital Inputs Configuration Guide
Manufacturing Standards
Electromagnetic compati ility
This instrument has been designed to comply with the standards and regulations set down
by the European EMC Directive 2004/108/EC using BS EN 61326: 2006
Safety
This instrument has been designed to comply with the standards and regulations set down
by the European Low Voltage Directive 2006/95/EC using BS EN 61010-1: 2001
Quality
This instrument has been manufactured under the following quality standard:
ISO 9001:2008. Certificate No: FM 13843
Note: The standards referred to in the design and construction of LTH products are those
prevailing at the time of product launch. As the standards are altered from time to time, we
reserve the right to include design modifications that are deemed necessary to comply
with the new or revised regulations.
Contents
MXD70 Setpoints, Current Outputs,
and Digital Inputs Configuration Guide
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Contents
reface.........................................................................................................................1
Contents .....................................................................................................................3
Setpoints ....................................................................................................................5
Input Source........................................................................................................6
Trigger...................................................................................................................6
Mode......................................................................................................................9
Hysteresis.......................................................................................................... 10
Setpoint Dose Alarm..................................................................................... 11
Setpoint roportional Mode...................................................................... 14
Setpoint Alarm Mode................................................................................... 16
Setpoint Cleaning Mode ............................................................................. 17
Current Outputs ................................................................................................... 21
Current Output Calibration........................................................................ 24
Resetting the current Output user Calibration................................... 26
Digital Inputs ......................................................................................................... 29
Offline................................................................................................................. 30
Clean................................................................................................................... 31
Range Changing............................................................................................. 31
Switch Setup.................................................................................................... 31
Calibration ........................................................................................................ 32
CI ........................................................................................................................ 32
olarity ............................................................................................................... 32
Simulate Channels............................................................................................... 33
Index ......................................................................................................................... 36
Contents
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MXD70 Setpoints, Current Outputs, and
Digital Inputs Configuration Guide
Blank
Setpoints
MXD70 Setpoints, Current Outputs,
and Digital Inputs Configuration Guide
- 5 -
Setpoints
Setpoints
The MXD70 Series can be fitted with up to six setpoint relays designated 1 – 6. Setpoints 1 – 4 are
“Change Over” relays while 5 – 6 are “Normally Open” relays. Each individual setpoint can be assigned
to any one of the Sensor Input Channels. The Setpoint/Relays menu contains all of the necessary setup
functions to configure the setpoint sources. The instrument indicates the status of the enabled
setpoints by means of 6 LED indicators located above the main instrument display. A lit LED indicates
that the setpoint / Relay is active. If the LED is blinking it indicates a dose alarm has occurred on that
setpoint.
Main Menu
From the front screen press the menu button to
show the main menu options and select
Setpoint/Relays.
/ – Select Option
EXIT – Return to Front Screen
– Enter Option
Setpoints / Relays Setup
Select the Setpoint you wish to edit.
/ – Select Option
EXIT – Return to Main Menu
– Enter Option
Channel
The “Sensor Input Channel” the setpoint is to be
associated with. The channels shown depend on the
configuration of the instrument. For more
information regarding the Unit Alarm option see the
setpoint alarm mode section.
To disable the setpoint select the disabled option.
This will turn off the setpoint and clear any error
messages associated with it.
/ – Select Option
EXIT – Cancel
– Save Selection
Setpoints
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MXD70 Setpoints, Current Outputs, and
Digital Inputs Configuration Guide
Setpoints
Input Source
The input source for the selected setpoint.
Available options vary depending on whether the
appropriate source is enabled in the channel’s setup
menu.
Alarm option – see the setpoint alarm mode section.
Cleaning option – see the setpoint cleaning mode
section (not available on all input card types.)
/ – Select Option
EXIT – Cancel
– Save Selection
Range
The setpoint’s operating range.
This is only available if the associated Sensor Input
Channel has a range option and is set to Auto in the
channel’s setup menu.
The available options will depend on the cell
constant of the sensor used, consult the input card’s
manual for more information.
/ – Select Option
EXIT – Cancel
– Save Selection
Trigger
The setpoints can be configured to trigger in the
following ways:
High
Low
Band
Latch High
Latch Low
US (Conductivity Only – see Conductivity manual
for information)
/ – Select Option
EXIT – Cancel
– Save Selection
Setpoints
MXD70 Setpoints, Current Outputs,
and Digital Inputs Configuration Guide
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Setpoints
High
The setpoint will activate when the associated Sensor
Input Channel’s input becomes greater than the
setpoint level.
Low
The setpoint will activate when the associated Sensor
Input Channel’s input becomes less than the setpoint
level.
Band
The setpoint will activate when the associated Sensor
Input Channel’s input is either greater than the
setpoint high level or less than the setpoint low level.
Latch Hi
The setpoint will activate when the associated Sensor
Input Channel’s input is greater than the setpoint
high level and will remain active until the input falls
below the setpoint low level. It will then remain
inactive until the input level rises above the setpoint
high level.
Setpoints
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MXD70 Setpoints, Current Outputs, and
Digital Inputs Configuration Guide
Setpoints
Latch Low
The setpoint will activate when the associated Sensor
Input Channel’s input is less than the setpoint low
level and will remain active until the input rises
above the setpoint high level. It will then remain
inactive until the input level falls below the setpoint
low level.
High Value
The Setpoint High value.
/ – Increase / Decrease Digit
– Select Next Digit
EXIT – Cancel
– Save Value
Low Value
The Setpoint Low value.
/ – Increase / Decrease Digit
– Select Next Digit
EXIT – Cancel
– Save Value
Setpoints
MXD70 Setpoints, Current Outputs,
and Digital Inputs Configuration Guide
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Setpoints
Mode
The Setpoints can operate in one of three modes.
On/Off Mode – The setpoint energises when the
setpoint is activated and de-energises when the
setpoint is de-activated.
ulse roportional – See Setpoint proportional
Mode Section.
Time roportional – See Setpoint proportional
Mode Section.
/ – Select Option
EXIT – Cancel
– Save Selection
Delay
In order to prevent short duration changes at the
input affecting the setpoint operation a delay can be
set before the setpoint is energised. If the input is
still the same after the delay, then the setpoint will be
energised.
Note- Only available when Trigger is set to High or
Low and Mode is On/Off.
/ – Increase / Decrease Digit
– Select Next Digit
EXIT – Cancel
– Save Value
Setpoints
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MXD70 Setpoints, Current Outputs, and
Digital Inputs Configuration Guide
Setpoints
Hysteresis
A facility to apply hysteresis to the setpoint level
allows the user to avoid setpoint “Chatter” when the
sensor input level approaches the setpoint level.
“Chatter” is caused when the sensor input is
sufficiently close to the set point value and noise on
the signal repeatedly crosses the set point level, thus
causing the relay to switch on and off rapidly.
The hysteresis level should therefore be set to be
greater than the input noise level.
The Hysteresis value is a percentage of the setpoint
value applied both + and – to the setpoint. For
example, if the setpoint was 10.00 and the Hysteresis
was 1% then the hysteresis band would operate from
9.90 to 10.10.
Hysteresis operates as follows:
Trigger High – The setpoint is inactive until the
reading is greater than the Setpoint High + (Setpoint
High X Hysteresis %). It remains active until it goes
below Setpoint High – (Setpoint High X Hysteresis %).
Trigger Low – The setpoint is inactive until the
reading is less than the Setpoint Low - (Setpoint Low
X Hysteresis %). It remains active until it goes above
Setpoint Low + (Setpoint Low X Hysteresis %).
Trigger Band – The setpoint uses both high and low.
Note. Hysteresis is only available when setpoint
trigger is set to High, Low or Band.
/ – Increase / Decrease Digit
– Select Next Digit
EXIT – Cancel
Setpoint Trigger: High – Hysteresis
Setpoint Trigger: Low – Hysteresis
– Save Value
Setpoints
MXD70 Setpoints, Current Outputs,
and Digital Inputs Configuration Guide
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Setpoints
Setpoint Dose Alarm
The dose alarm timer can be used to prevent overdosing under many different fault conditions, such as
sensor failure or application problems.
Dose Alarm
Enable the dose alarm for the selected setpoint.
/ – Select Option
EXIT – Cancel
– Save Selection
Alarm Time
Sets the time which if the setpoint is active for longer
than causes the dose alarm to activate.
During pulse or time proportional mode the
cumulative “on” time that the setpoint is active will
be measured.
/ – Increase / Decrease Digit
– Select Next Digit
EXIT – Cancel
– Save Value
Dose Alarm Active
When the dose alarm activates the following
happens:-
The setpoint will de-energise.
The associated setpoint led will flash.
The Dose Alarm error message will appear next to
the associated input channel on the front screen.
ACK will appear as a function to acknowledge the
setpoint on the front screen.
An error will be set for that input channel.
ACK – Enter Setpoint Acknowledge Menu
/
– Scroll Around Menus
Menu – Access Main Menu
Setpoints
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MXD70 Setpoints, Current Outputs, and
Digital Inputs Configuration Guide
Setpoints
Dose Alarm Acknowledge
To cancel the dose alarm and reactivate the setpoint,
select the required setpoint from the shown list and
press enter.
Note – If, once reset, the setpoint again remains
energised for the length of the dose alarm timer then
the dose alarm will once again activate. If this
problem persists then a dosing problem will need to
be investigated.
/ – Select Option
EXIT – Cancel
– Save Selection
Initial Charge
This allows the user to have a one time over-ride of
the Dose Alarm to use for example when filling a tank
for the first time.
The user enters a charge time and then initiates the
charge time. The unit will then disable the dose alarm
until either the relay becomes inactive because the
setpoint has been reached or the charge timer
reaches zero in which event the unit will
automatically display a Dose Alarm.
/ – Select Option
EXIT – Cancel
– Save Selection
Charge Time
Sets the initial charge time.
/ – Increase / Decrease Digit
– Select Next Digit
EXIT – Cancel
– Save Value
Setpoints
MXD70 Setpoints, Current Outputs,
and Digital Inputs Configuration Guide
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Setpoints
Initial Charge Access
Enabling this allows the user to initialise the initial
charge by means of a menu on the front screen.
/ – Select Option
EXIT – Cancel
– Save Selection
Front Screen Initial Charge
Enter the Initial Charge Menu by means of the INIT
button.
INIT – Enter Initial Charge Menu
/
– Scroll Around Menus
Menu – Access Main Menu
Initialise Initial Charge
Select which setpoint to initialise the initial charge.
Note – Once started the Initial charge timer will
appear next to the associated input channel on the
front screen.
/ – Select Option
EXIT – Cancel
– Save Selection
Start Initial Charge
The user can also start the initial charge via this
option in the setpoint menu.
Note – Once started the Initial charge timer will
appear next to the associated input channel on the
front screen.
/ – Select Option
EXIT – Cancel
– Save Selection
Setpoints
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MXD70 Setpoints, Current Outputs, and
Digital Inputs Configuration Guide
Setpoints
Setpoint Proportional Mode
In addition to On/Off mode the MXD70 Series also provides two forms of pseudo proportional control,
which can be used to control the levels to a defined value when used in conjunction with a pump or
valve. When the reading deviates from the programmed set point level the relay pulses at a rate
proportional to that deviation. Note – Only available when Setpoint Trigger is set to either High or Low.
Pulse Proportional Mode
The ulse roportional mode is intended to drive solenoid type dosing pumps which have the facility
to accept an external pulse input. The setpoint relay operates by producing a pulse of 0.2 seconds in
duration and with a maximum period of one pulse per 30 seconds. The pulse rate increases as the
measurement moves further from the set point, until it reaches the minimum period of one pulse per
0.4 seconds at the limit of the proportional band.
For example if the user sets a proportional band of 1.00, the setpoint trigger to LOW, and a setpoint
value of 10.00. When the reading falls just below 10.00 the setpoint will begin to pulse at its longest
period of once per 30 seconds. As the reading falls further from the setpoint the period will decrease
until it reaches its minimum of one pulse every 0.4 seconds at the limit of the proportional band. (See
Setpoint ulse Rate – ulse roportional Mode section on the diagram below.)
Time Proportional Mode
Time roportional Mode allows a user defined cycle time to control any on/off device such as a
solenoid valve or dosing pump over a user set proportional band.
For example if the user sets a proportional band of 1.00, the setpoint trigger to LOW, and a setpoint
value of 10.00. When the reading falls below 9.00 the setpoint would be energised 100% of the cycle
time. As the input rises and approaches the set point the setpoint starts to cycle on and off with the on
time reducing and the off time increasing, respectively until it reached the setpoint and would be off
for 100% of the cycle time. The cycle time is adjustable and is the sum of the on and off times. (See
Setpoint Cycle Time – Time roportional Mode section on the diagram below.)
Setpoints
MXD70 Setpoints, Current Outputs,
and Digital Inputs Configuration Guide
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Setpoints
Cycle Time
Sets the cycle time (sum of both On and Off periods).
Note – Time roportional mode only.
/ – Increase / Decrease Digit
– Select Next Digit
EXIT – Cancel
– Save Value
Proportional Band
Enter the size of the proportional band in
measurement units.
/ – Increase / Decrease Digit
– Select Next Digit
EXIT – Cancel
– Save Value
Setpoints
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MXD70 Setpoints, Current Outputs, and
Digital Inputs Configuration Guide
Setpoints
Setpoint Alarm Mode
By Selecting Alarm in the setpoints input source the setpoint can be configured as an alarm output
triggered by one of a number of events.
Sensor Error – When a sensor related error is detected on the associated sensor input
channel.
Dose Alarm – When any of the dose alarms active on a setpoint associated with this
setpoints sensor input channel.
Cali ration – When a calibration is in progress on the associated sensor input channel.
Off-Line – When the associated sensor input channel has been taken “Off-Line.”
Any Error – When any error is detected on the associated sensor input channel.
Cleaning – When a cleaning operation is in progress on a setpoint associated with
this setpoints sensor input channel.
Cali ration Due –
When if enabled the calibration due timer has expired on the associated
sensor input channel.
Gain Error – When a gain error is present on the associated sensor input channel.
Only available when set to a suspended solids input channel.
Note – By selecting Unit Alarm in the setpoint channel option each alarm option will activate if they
occur on any of the instruments three sensor input channels.
Setpoints
MXD70 Setpoints, Current Outputs,
and Digital Inputs Configuration Guide
- 17 -
Setpoints
Setpoint Cleaning Mode
The Setpoints can be configured to operate a jet spray wash or rotary electrode cleaning system on a
timed cycle. Its purpose is to prevent accumulation of particulate matter on the active surfaces of the
sensor. Note that cleaning is not available on all sensor input types.
Input Source
If available select cleaning from the list of options.
/ – Select Option
EXIT – Cancel
– Save Selection
Clean Duration
Enter the duration of the cleaning operation.
For the duration of the clean, cleaning will appear in
the associated sensor input display section on the
front screen.
/ – Increase / Decrease Digit
– Select Next Digit
EXIT – Cancel
– Save Value
Clean Interval
Enter the time between cleaning operations.
/ – Increase / Decrease Digit
– Select Next Digit
EXIT – Cancel
– Save Value
Setpoints
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MXD70 Setpoints, Current Outputs, and
Digital Inputs Configuration Guide
Setpoints
Time Remaining
Shows the time remaining till the next clean
operation.
Note – Cannot be edited.
Clean Mode
Associated sensor input channel state when cleaning.
It is recommended that off-line is selected. This will
automatically take the associated sensor input
channel offline, de-energise associated setpoints and
hold associated current outputs, during a clean
operation. This will prevent any undesired control
actions resulting from spraying cleaning solution
onto the sensor.
/ – Select Option
EXIT – Cancel
– Save Selection
Clean Recovery
If cleaning “Off-line” then the user can introduce an
additional post cleaning delay before coming back
“On-line”, this provides the sensor a period to
stabilise.
/ – Increase / Decrease Digit
– Select Next Digit
EXIT – Cancel
– Save Value
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