Metrohm 893 User manual

893 Professional Biodiesel Rancimat
Manual
8.893.8001EN / 2020-01-28

Metrohm AG
CH-9100 Herisau
Switzerland
Phone [phone]
Fax [phone]
[email protected]
www.metrohm.com
893 Professional Biodiesel Rancimat
Manual
8.893.8001EN / 2020-01-28

Technical Communication
Metrohm AG
CH-9100 Herisau
[email protected]
This documentation is protected by copyright. All rights reserved.
This documentation has been prepared with great care. However, errors
can never be entirely ruled out. Please send comments regarding possible
errors to the address above.

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ Table of contents
893 Professional Biodiesel Rancimat ￭￭￭￭￭￭￭￭ III
Table of contents
1 Introduction 1
1.1 Instrument description ......................................................... 1
1.2 About the documentation ................................................... 2
1.2.1 Symbols and conventions ........................................................ 2
1.3 Safety instructions ................................................................ 3
1.3.1 General notes on safety ........................................................... 3
1.3.2 Electrical safety ........................................................................ 3
1.3.3 Flammable solvents and chemicals ........................................... 5
1.3.4 Recycling and disposal ............................................................. 5
2 Overview of the instrument 6
2.1 Front of the instrument ........................................................ 6
2.2 Rear of the instrument ......................................................... 7
2.3 Instrument display ................................................................ 8
3 Installation 10
3.1 Setting up the instrument .................................................. 10
3.1.1 Packaging .............................................................................. 10
3.1.2 Checks .................................................................................. 10
3.1.3 Location ................................................................................ 10
3.2 Mounting accessories ......................................................... 11
3.2.1 Mounting the internal air supply ............................................ 11
3.2.2 Mounting the external air supply ........................................... 13
3.2.3 Assembling the reaction and measuring vessels ..................... 14
3.2.4 Inserting vessels / Establishing tubing connections ................. 17
3.2.5 Mounting the exhaust air collection tube ............................... 18
3.3 Power connection ............................................................... 19
3.3.1 Connecting the power cord to the energy supply ................... 19
3.3.2 Replacing fuses ...................................................................... 20
3.3.3 Switching the instrument on and off ...................................... 21
3.4 Connecting a computer ...................................................... 22
3.4.1 Connecting the 893 Professional Biodiesel Rancimat and the
computer .............................................................................. 22
4 Operation 24
4.1 Rancimat method ............................................................... 24
4.2 Calibration functions .......................................................... 25
4.2.1 Determining the cell constant ................................................ 25
4.2.2 Determining the temperature correction ................................ 26

Table of contents ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
IV ￭￭￭￭￭￭￭￭ 893 Professional Biodiesel Rancimat
4.3 Determinations ................................................................... 29
4.3.1 Preparing the instrument and the accessories ......................... 29
4.3.2 Preparing the determination .................................................. 30
4.3.3 Cleaning the accessories ........................................................ 32
4.3.4 Cleaning the oil separator ...................................................... 33
5 Operation and maintenance 36
5.1 General notes ...................................................................... 36
5.1.1 Care ...................................................................................... 36
5.1.2 Maintenance by Metrohm Service .......................................... 36
5.1.3 Cleaning the instrument ........................................................ 37
5.2 Replacing the dust filter .................................................... 38
5.3 Regenerating or replacing the molecular sieve ............... 39
6 Troubleshooting 40
6.1 Problems .............................................................................. 40
7 Technical specifications 45
7.1 General data ........................................................................ 45
7.2 Temperature control and measurement ........................... 45
7.3 External temperature sensor ............................................. 46
7.4 Conductivity measurement ................................................ 46
7.5 Gas flow regulation ............................................................ 47
7.6 USB interface ...................................................................... 47
7.7 Power socket ...................................................................... 47
7.8 Ambient temperature ......................................................... 47
7.9 Dimensions/Material .......................................................... 48
8 Accessories 49
Index 50

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ Table of figures
893 Professional Biodiesel Rancimat ￭￭￭￭￭￭￭￭ V
Table of figures
Figure 1 Front 893 Professional Biodiesel Rancimat ......................................... 6
Figure 2 893 Professional Biodiesel Rancimat rear ........................................... 7
Figure 3 Instrument display ............................................................................. 8
Figure 4 Mounting accessories for the air supply ........................................... 11
Figure 5 Drying flask - Individual parts ........................................................... 12
Figure 6 Drying flask mounted in place ......................................................... 13
Figure 7 Equipping the reaction and measuring vessels ................................. 15
Figure 8 Mounting the air tube: correct - incorrect ........................................ 17
Figure 9 Mounting the foam barrier .............................................................. 17
Figure 10 Instrument display with instrument name ........................................ 21
Figure 11 Instrument display with "no connection" symbol ............................. 21
Figure 12 Instrument display without instrument name and symbol ................ 22
Figure 13 Instrument display with serial number ............................................. 22
Figure 14 Measuring arrangement (schematic representation) ......................... 25
Figure 15 Assembling the reaction vessel for determining the temperature correc-
tion ................................................................................................. 27
Figure 16 Oil separator (6.2753.200), disassembled ........................................ 34
Figure 17 Dust filter - conditions ..................................................................... 38

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 1 Introduction
893 Professional Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 1
1 Introduction
1.1 Instrument description
The 893 Professional Biodiesel Rancimat is a computer-controlled measur-
ing device for determining the oxidation stability of biodiesel and biodiesel
blends (mixture of biodiesel and conventional diesel fuel) according to the
standards EN 14112 and EN 15751.
It is equipped with two heating blocks each with 4 measuring positions.
Each block can be heated individually, i.e., 4 samples can each be mea-
sured at two different temperatures or 8 samples at the same tempera-
ture. The measurements at the individual measuring positions can be
started individually for this.
The 893 Professional Biodiesel Rancimat is controlled by means of the
StabNet computer software and a computer that is connected via the
USB interface. Up to 4 instruments can be controlled and monitored by
each computer, hence allowing a maximum of 32 samples to be analyzed
at the same time. The evaluation algorithm of the computer software
determines the break point of the Rancimat curve and thus the induction
time fully automatically. Besides the induction time, the so-called stabil-
ity time, i.e., the time until a defined conductivity change has been
achieved, can also be determined. In the case of conductivity changes
(stages) which do not have anything to do with the autoxidation, the eval-
uation can be suspended for definite time intervals. The results deter-
mined can be further processed mathematically.
Each Rancimat curve can also be evaluated manually. A computer-sup-
ported tangential method is available for this, in which you can position
the tangents anywhere on your curves. This makes evaluations possible in
extreme cases as well.
The results of the determinations are saved in a database together with all
method and determination data. Determinations can be searched for,
sorted, filtered, exported and printed in the Database program part.
Apart from graphically displaying individual and multiple curves, the soft-
ware is also capable of conducting recalculations with changed parame-
ters and extrapolating the results to a certain temperature.

1.2 About the documentation ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
2￭￭￭￭￭￭￭￭ 893 Professional Biodiesel Rancimat
1.2 About the documentation
CAUTION
Please read through this documentation carefully before putting the
instrument into operation. The documentation contains information
and warnings which the user must follow in order to ensure safe opera-
tion of the instrument.
1.2.1 Symbols and conventions
The following symbols and formatting may appear in this documentation:
Cross-reference to figure legend
The first number refers to the figure number, the sec-
ond to the instrument part in the figure.
Instruction step
Carry out these steps in the sequence shown.
Method Dialog text, parameter in the software
File ▶ New Menu or menu item
[Next] Button or key
WARNING
This symbol draws attention to a possible life-threat-
ening hazard or risk of injury.
WARNING
This symbol draws attention to a possible hazard due
to electrical current.
WARNING
This symbol draws attention to a possible hazard due
to heat or hot instrument parts.
WARNING
This symbol draws attention to a possible biological
hazard.
CAUTION
This symbol draws attention to possible damage to
instruments or instrument parts.

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 1 Introduction
893 Professional Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 3
NOTE
This symbol highlights additional information and
tips.
1.3 Safety instructions
1.3.1 General notes on safety
WARNING
Operate this instrument only according to the information contained in
this documentation.
This instrument exhibited no flaws in terms of technical safety at the time
it left the factory. To preserve this status and ensure non-hazardous opera-
tion of the instrument, the following instructions must be observed care-
fully.
Hot reaction vessels
WARNING
The reaction vessels can become very hot.
Avoid any contact with the hot reaction vessels. Place these in the ves-
sel holders provided for cooling down.
Flammable substances
WARNING
The heating block of the 893 Professional Biodiesel Rancimat can be
heated to 159.9 °C.
Flammable substances may ignite at such temperatures.
Adjust the oven's maximum heating temperature to the sample that is
to be analyzed.
1.3.2 Electrical safety
The electrical safety when working with the instrument is ensured as part
of the international standard IEC 61010.

1.3 Safety instructions ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
4￭￭￭￭￭￭￭￭ 893 Professional Biodiesel Rancimat
WARNING
Only personnel qualified by Metrohm are authorized to carry out service
work on electronic components.
WARNING
Never open the housing of the instrument. The instrument could be
damaged by this. There is also a risk of serious injury if live components
are touched.
There are no parts inside the housing which can be serviced or replaced
by the user.
Supply voltage
WARNING
An incorrect supply voltage can damage the instrument.
Only operate this instrument with a supply voltage specified for it (see
rear panel of the instrument).
Protection against electrostatic charges
WARNING
Electronic components are sensitive to electrostatic charges and can be
destroyed by discharges.
Do not fail to pull the power cord out of the power socket before you
set up or disconnect electrical plug connections at the rear of the
instrument.

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 1 Introduction
893 Professional Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 5
1.3.3 Flammable solvents and chemicals
WARNING
All relevant safety measures are to be observed when working with
flammable solvents and chemicals.
￭Set up the instrument in a well-ventilated location (e.g. fume cup-
board).
￭Keep all sources of flame far from the workplace.
￭Clean up spilled liquids and solids immediately.
￭Follow the safety instructions of the chemical manufacturer.
1.3.4 Recycling and disposal
This product is covered by European Directive 2012/19/EU, WEEE – Waste
Electrical and Electronic Equipment.
The correct disposal of your old instrument will help to prevent negative
effects on the environment and public health.
More details about the disposal of your old instrument can be obtained
from your local authorities, from waste disposal companies or from your
local dealer.

2.1 Front of the instrument ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
6￭￭￭￭￭￭￭￭ 893 Professional Biodiesel Rancimat
2 Overview of the instrument
2.1 Front of the instrument
1
2
3
4
5
6
7
8
Figure 1 Front 893 Professional Biodiesel Rancimat
1Iso-Versinic® tubing (6.1839.000)
For connecting the reaction vessel to the
measuring vessel. A fluoroelastomer.
2Measuring vessel cover (6.0913.130)
Contains an integrated conductivity measur-
ing cell.
3Glass measuring vessel (6.1428.030) 4Instrument display
Displays the status of the instrument and the
individual measuring positions.
5FEP tubing 250 mm (6.1805.080)
For supplying air into the reaction vessel.
6Reaction vessel cover (6.2753.107)
7Reaction vessels (6.1429.050) 8Start buttons

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 2 Overview of the instrument
893 Professional Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 7
2.2 Rear of the instrument
Figure 2 893 Professional Biodiesel Rancimat rear
1Electrode connector
For connecting the conductivity measuring
cell integrated in the measuring vessel cover.
2Air supply connector
For connecting the FEP tubing 250 mm.
3Power switch
For switching the instrument on and off.
I = ON / 0 = OFF.
4Fuse holder
For replacing fuses (see chapter 3.3.2, page
20).
5Power socket
For important information on the power
connection, see Chapter 3.3.
6Collection tube holder
For fastening the optional exhaust air collec-
tion tube (6.2757.000).
7Drying flask cap (6.1602.145)
Cap for the drying flask.
8Bottle holder
For fastening the drying flask.
9Drying flask (6.1608.050)
Drying flask filled with molecular sieve
(6.2811.000).
10 "Air out" connector
11 FEP tubing 130 mm (6.1805.010)
For connecting the Air out connector to the
Air/N2 in connector during normal opera-
tion with the internal air pump.
12 "Air/N2 in" connector

2.3 Instrument display ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
8￭￭￭￭￭￭￭￭ 893 Professional Biodiesel Rancimat
13 Type plate
Contains specifications concerning supply
voltage and serial number.
14 Pt100 connector
For connecting an external temperature sen-
sor.
15 Dust filter (6.2724.010) 16 USB connector
For connecting the computer.
17 "To flask" connector 18 FEP tubing 250 mm (6.1805.080)
For supplying the air from the internal pump
to the drying flask.
19 "From flask" connector 20 FEP tubing 250 mm (6.1805.080)
For supplying the air from the drying flask to
the reaction vessels.
2.3 Instrument display
893_1
1 2 3 4
9 8 7 6
10 5
Figure 3 Instrument display
1Measuring vessel cover red
This measuring position is not available for a
determination (determination is running or
multiple determination has not yet been
completed).
2Measuring vessel cover green
A determination can be started on this mea-
suring position.
3Instrument name
The instrument name display corresponds to
the configuration in StabNet.
4Measuring vessel cover gray
This measuring position is not available for
starting a determination (instrument not
connected to computer or no method loa-
ded).

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 2 Overview of the instrument
893 Professional Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 9
5Conductivity display block B
Shows the measured conductivity.
Dash (-) is displayed = Conductivity cannot
be displayed (no sensor connected or no
valid measuring signal).
6Gas flow display block B
Shows the gas flow measured on block B
(gray background: gas flow switched off;
white background: gas flow switched on).
7Temperature display block B
Shows the temperature measured on block
B (gray background: heater switched off; red
background: temperature not stable; green
background: temperature stable).
8Temperature display block A
Shows the temperature measured on block
A (gray background: heater switched off;
red background: temperature not stable;
green background: temperature stable).
9Gas flow display block A
Shows the gas flow measured on block A
(gray background: gas flow switched off;
white background: gas flow switched on).
10 Conductivity display block A
Shows the measured conductivity.
Dash (-) is displayed = Conductivity cannot
be displayed (no sensor connected or no
valid measuring signal).

3.1 Setting up the instrument ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
10 ￭￭￭￭￭￭￭￭ 893 Professional Biodiesel Rancimat
3 Installation
3.1 Setting up the instrument
3.1.1 Packaging
The instrument is supplied in protective packaging together with the sepa-
rately packed accessories. Keep this packaging, as only this ensures safe
transportation of the instrument.
3.1.2 Checks
Immediately after receipt, check whether the shipment has arrived com-
plete and without damage by comparing it with the delivery note.
3.1.3 Location
CAUTION
Heat accumulation
Placing the instrument in a tight space or covering the housing may
lead to overheating and subsequently damage the instrument.
￭Set the instrument up freestanding, to allow the air to circulate
around the instrument.
￭Do not cover the instrument.
The instrument has been developed for operation indoors and may not be
used in explosive environments.
Place the instrument in a location of the laboratory which is suitable for
operation and free of vibrations and which provides protection against
corrosive atmosphere and contamination by chemicals to the extent possi-
ble.
The instrument should be protected against excessive temperature fluctua-
tions and direct sunlight.
NOTICE
In order to improve accessibility of the measuring positions, the instru-
ment can also be placed on the optionally available turning ring
(6.2059.000).

￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭ 3 Installation
893 Professional Biodiesel Rancimat ￭￭￭￭￭￭￭￭ 11
3.2 Mounting accessories
3.2.1 Mounting the internal air supply
The gas in the 893 Professional Biodiesel Rancimat is normally supplied
using the internal air pump, which aspirates laboratory air. For air
supply and air purification, the following accessories must be mounted on
the rear of the 893 Professional Biodiesel Rancimat:
1 2 3 4 5 6 7 8
9
10
11
12
Figure 4 Mounting accessories for the air supply
1FEP tubing 130 mm (6.1805.010) 2"Air out" connector
3"Air/N2 in" connector 4Dust filter (6.2724.010)
5"From flask" connector 6FEP tubing 250 mm (6.1805.080)
For supplying the air from the drying flask to
the reaction vessel.
7"To flask" connector 8FEP tubing 250 mm (6.1805.080)
For supplying the air from the internal pump
to the drying flask.
9Drying flask cap (6.1602.145)
Cap for the drying flask.
10 Drying flask (6.1608.050)
Drying flask filled with molecular sieve
(6.2811.000).
11 Bottle holder
For fastening the drying flask.
12 Filter tube (6.1821.040)
Mount the accessories for the air supply as follows:
1Mounting the dust filter
￭Insert the dust filter on the connector marked with Filter on the
rear of the 893 Professional Biodiesel Rancimat.
￭If the laboratory air is heavily contaminated, a tubing for supply-
ing fresh air can be connected to the dust filter.

3.2 Mounting accessories ￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭￭
12 ￭￭￭￭￭￭￭￭ 893 Professional Biodiesel Rancimat
NOTICE
The dust filter serves for filtering the air aspirated through the air
pump and must be replaced at periodic intervals (see chapter 5.2,
page 38).
2Mounting the drying flask
I II III
1
2
3
Figure 5 Drying flask - Individual parts
1Drying flask cap (6.1602.145) 2Filter tube (6.1821.040)
3Bottle (6.1608.050)
￭[I] – Fill the molecular sieve (6.2811.000) into the drying flask.
￭[II] – Screw the filter tube on the bottom side of the drying flask
cap into the opening marked with a dot (on the upper side).
￭[III] – Screw the drying flask cap with mounted filter tube onto
the drying flask and insert it in the flask holder on the rear of the
893 Professional Biodiesel Rancimat.
￭Screw one end of the FEP tubing 250 mm to the opening on the
drying flask cap marked with a dot.
￭Screw the other end of the FEP tubing to the From flask connec-
tor on the rear of the 893 Professional Biodiesel Rancimat.
￭Screw one end of the second FEP tubing 250 mm to the second
opening on the drying flask cap.
￭Screw the other end of the second FEP tubing to the To flask
connector.