KERN & Sohn GmbH Ziegelei 1 D-72336 Balingen E-Mail: info@kern-sohn.com Tel: +49-[0]7433- 9933-0 Fax: +49-[0]7433-9933-149 Internet: www.kern-sohn.com Operating instruction Precision balances KERN EW/EG-N/EWB Version 2.
GB KERN EW/EG-N/EWB Version 2.6 03/2012 Operating instruction Precision balances Table of contents 1 Technical data ............................................................................................ 4 1.1 1.2 Read-off of the various weighing units ........................................................................... 10 Weighing unit conversion charts ..................................................................................... 11 2 Fundamental information (general) ...........
6 Operation .................................................................................................. 27 6.1 6.1.1 6.1.2 6.2 6.2.1 Operating elements ............................................................................................................ 27 Overview of the keypad ........................................................................................................ 28 Overview of display .......................................................................................
1 Technical data KERN EG 220-3NM EG 420-3NM EG 620-3NM Readout 0,001 g 0,001 g 0,001 g Verification value (e) 0,01 g 0,01 g 0,01 g Weighing range (max.
KERN EG 2200-2NM EG 4200-2NM EW 120-4NM Readout 0,01 g 0,01 g 0,0002 g Verification value (e) 0,1 g 0,1 g 0,001 g 2200 g 4200 g 120 g II II I 2200 g 4200 g 120g Minimum load (Min) 0,5 g 0,5 g 0,02 g Minimum weight for counting parts 0,01 g 0,01 g - 10, 30, 50, 100 10, 30, 50, 100 - 0,01 g 0,01 g 0,0002 g ± 0, 02 g ± 0,02 g ± 0,0008 g internal internal - Test weight, included - - 50 g (F1) Recommended adjusting weight, not included (class) - - 100g (E2) 3 sec.
KERN EW 220-3NM EW 420-3NM EW 620-3NM Readout 0,001 g 0,001 g 0,001 g Verification value (e) 0,01 g 0,01 g 0,01 g Weighing range (max.
KERN EW 820-2NM EW 2200-2NM EW 4200-2NM Readout 0,01 g 0,01 g 0,01 g Verification value (e) 0,01 g 0,1 g 0,1 g Weighing range (max.) 820 g 2200 g 4200 g I II II 820 g 2200 g 4200 g 1g 0,5 g 0,5 g 0,01 g 0,01 g 0,01 g 10, 30, 50, 100 10, 30, 50, 100 10, 30, 50, 100 0,01 g 0,01 g 0,01 g ± 0,01 g ± 0,02 g ± 0,02 g 1 x 200 g + 1 x 500 g(F1) 2000 g (F1) 2 x 2 kg (E2) 2 sec. 2 sec. 2 sec.
KERN EW 6200-2NM EW 12000-1NM Readout 0,01 g 0,1 g Verification value (e) 0,1 g 1g 6 200 g 12 000 g I II 6 200 g 12 000 g 1g 5g 0,01 g 0,1 g 10, 30, 50, 100 10, 30, 50, 100 0,02 g 0,1 g Linearity ± 0, 03 g ± 0,1 g Recommended adjusting weight, not included (class) 5 kg (E2) 10 kg (F1) 3 sec. 3 sec. 2,8 2,8 Weighing range (max.
KERN EWB 220-2M EWB 620-2M EWB 1200-1M Readout 0,01 g 0,01 g 0,1 g Verification value (e) 0,01 g 0,1 g 0,1 g Weighing range (max.
1.1 Read-off of the various weighing units Weighing unit g (ct) (oz) (lb) (ozt) (dwt) (grain) (Hong Kong) (Singapore,Malaysia) (Taiwan) mom (to) Weighing unit g (ct) (oz) (lb) (ozt) (dwt) (Hong Kong) (Singapore,Malaysia) (Taiwan) mom (to) Weighing unit g (ct) (oz) (lb) (ozt) (dwt) (Hong Kong) (Singapore,Malaysia) (Taiwan) mom (to) 10 EW 120-4NM EG 220-3NM / EW 220-3NM 0.001 0.01 0.0001 0.00001 0.0001 0.001 0.1 0.0001 0.0001 0.0001 0.001 0.0001 EG 420-3NM / EW 420-3NM 0.001 0.01 0.0001 0.00001 0.
Weighing unit g (ct) (oz) (lb) (ozt) (dwt) (Hong Kong) (Singapore,Malaysia) (Taiwan) mom (to) 1.2 EWB 220-2M EWB 620-2M EWB 1200-1M 0.01 0.1 0.001 0.0001 0.001 0.01 0.001 0.001 0.001 0.01 0.001 0.01 0.1 0.001 0.0001 0.001 0.01 0.001 0.001 0.001 0.01 0.001 0.1 1 0.01 0.001 0.01 0.1 0.01 0.01 0.01 0.1 0.
2 Fundamental information (general) 2.1 Intended use The balance you have acquired serves to determine the weighing value of the material to be weighed. It is intended to be used as a “non-automatic“ balance, i.e. the material to be weighed is manually and carefully placed in the centre of the weighing plate. The weighing value can be read off after a stable weighing value has been obtained. 2.2 Inappropriate use Do not use the balance for dynamic weighing.
2.4 Monitoring the test substances The metrology features of the balance and any possible available adjusting weight must be checked at regular intervals within the scope of quality assurance. For this purpose, the answerable user must define a suitable interval as well as the nature and scope of this check. Information is available on KERN’s home page (www.kernsohn.com) with regard to the monitoring of balance test substances and the test weights required for this.
5 Unpacking, installation and commissioning 5.1 Place of installation, place of use The balance is constructed in such a way that reliable weighing results can be achieved under normal application conditions. By selecting the correct location for your balance, you will be able to work quickly and precisely.
5.2 Unpacking Carefully remove the balance from its packaging, remove the plastic wrapping and position the balance in its intended working location. 5.2.1 Installation Use the foot screws to level the balance until the air bubble in the bubble level is in the prescribed circle. 5.2.2 List of items supplied Standard accessories: (1) Balance (2) Weighing plate (3) Weighing plate bracket (4) Windbreak (excl. EWB models) (5) Interface connector set (6) Operating instructions (excl.
5.2.3 Positioning the weighing plate Screw the bracket on tightly according to the drawing and subsequently attach the weighing plate. 5.2.
5.2.5 Draft shield installation – optional Remove the weighing plate and loosen the screws to remove the bracket. Use a screwdriver to loosen both screws to the left and right of the bracket guide and remove. Now place the draft shield to fit on the housing and and secure through the opened sliding doors using both screws. Screw the bracket on tightly according to the drawing and subsequently attach the weighing plate. 5.2.
5.3 Mains supply Electric power supply is by means of the external mains supply circuit. The printed voltage level must comply with the local voltage. Only use original KERN mains supply circuits. The use of other makes is subject to approval by KERN. Mains adaptor connection: Mains adaptor connection 5.4 Operation using a rechargeable battery (optional) Take off the weighing plate and remove the bracket by loosening the screw.
5.5 Connecting peripheral equipment The balance must be disconnected from the mains before connecting or disconnecting additional equipment (printer, PC) to or from the data interface (see chap. 8.) Only use KERN accessories and peripheral equipment with your balance. These have been ideally coordinated to your balance. 5.6 Initial start-up A warm-up time of 10 minutes stabilises the measured values after switching on. The accuracy of the balance depends on the local acceleration of the fall.
5.6.3 Stability indication ο 0 I I I F 0.000 g Stable 0 I I I F 0.000 g Unstable The balance is in a stable condition if the [ο] stability indication appears on the display. The [ο] indication disappears if the condition is unstable. Stable ambient conditions can be achieved by using the draft shield (See chap. 5.2.4 for installation) 5.6.4 Zero display on the balance Environmental influences can lead to the exact figure of “0.000“ not being displayed in spite of an empty weighing dish.
5.7 Adjustment As the acceleration value due to gravity is not the same at every location on earth, each balance must be coordinated – in compliance with the underlying physical weighing principle - to the existing acceleration due to gravity at its place of location ( only if the balance has not already been adjusted to the location in the factory). This adjustment process must be carried out at every start-up, after every change of location as well as in case of fluctuating environment temperature.
CAL Press buttons and at the same time and release at the same time, [WAIt]] is briefly displayed. WAit CAL After that [CAL.0] will appear flashing, Zero point will be saved. CAL. 0 After that [CAL.on] will appear. CAL CAL. on Rotate the turn knob on the right side of the balance in to position CAL. CAL CAL. on Adjustment is carried out automatically. [CAL.on] will appear flashing. The display changes [CAL.on] to [CAL.oFF] automatically The process of adjustment is completed.
Turn the adjusting knob on the right side of the balance to the WEIGH position. CAL buSY End. Calibration is now finalised. The balance will automatically return to weighing mode. 5.8.3 Adjusting with external weight (only KERN EW and EWB) Carry out adjustment with the recommended adjusting weight (see Chapter 1 „Technical Data“). The adjustment can also be carried out with different adjusting weights (see table), but not ideal from a metrological point of view.
Adjustment procedure: Check that the surrounding conditions are stable. A short warm-up time of about 10 minutes is recommended for stabilisation. Operation Switch on the balance using the Press and hold the Display key Func key until [ CAL] appears. Now release the key. CAL Press the key while holding down the key. Subsequently release both keys simultaneously. CAL on 0 CAL The zero point will be stored. on F.S Place the adjusting weight carefully on the centre of the weighing plate.
5.9 Verification General: According to the EU guideline 90/384/EEC balances must be verified if they are to be used as follows (legally regulated area): a) For commercial transactions if the price of goods is determined by weighing b) For the production of medines in pharmacies as well as for analyses in the medical and pharmaceutical laboratory c) For official purposes d) For the production of finished packages In case of doubt, please contact your local office of weights and measures.
5.10 Verification switch and official seal Prior to verification the verification switch must be moved from the displayed position (see direction of arrow) to verification position. Once in this position, a parenthesis will be displayed around the last display point. Following calibration the balance is sealed at the marked position. Balance calibration is not valid without the “official seals“.
6 Operation 6.1 Operating elements Draft shield Bubble level Display Keyboard Adjustable device feet Adjusting switch (KERN EG) EW/EG-N/EWB-e-1226 RS232C interface connection (excl.
6.1.
6.1.2 Overview of display Display g 0 ο * Pcs % mom M CAL Description Gramme Zero setting display Stability indication Power display (standby) Unit counter display (excl. EW 120-4NM) Percent weighing display (excl. EW 120-4NM) Tolerance weighing display (excl. EW 120-4NM) Momme Balance carry out balance function, e.g. unit count / display of stored value Calibration display. Signalises calibration procedure.
6.2 Operation 6.2.1 Weighing Display symbol: g Operation Display Press the key to switch on the balance. The balance will carry out a self-test. Your balance is ready to weigh as soon as the “0.000" display appears. Apply the item to be weighed. The weight value is displayed. A switch can be made from one unit to another, e.g. from ”g“ to another unit, for example ”ct“, by repeatedly pressing the key. Setting – see chapter 7 on “Functions“. [g] [ct] [Pcs] [%] [g] ……. g % 30 0 I I I F 0.
6.2.1.1 Underfloor weighing Objects which, because of their size or shape, cannot be put on the scale, can be weighed by means of underfloor weighing. Proceed as follows: Switch off the balance. Turn the balance over. Open the cover plate (1) on the base of the balance. Hang on the hanging loop (optional) completely for underfloor weighing. Place the balance over an opening. Hang the item to be weighed on the hanging loop and carry out weighing.
6.2.1.2 Tare weighing (tare) The empty weight of any weighing container can be tared at the push of a button, so that the net weight of the item to be weighed is displayed during subsequent weighings. Operation Display Place the empty tare container on the weighing plate. The total weight of the applied container is displayed. 0 I I I F 23.456 g Press the cedure. key to start the tare pro0 0 I I I F 0.000 g The weight of the container is now stored internally.
The tare procedure can be repeated as often as desired, for example when weighing several components into a mixture (weighing in). Press the ”0.000". key to set the display to 0 0 I I I F 0.000 g The total weight of the container is removed by taring. Apply further components to the weighing container (weighing in). 0 I I I F Now read off the weight of the added item to be weighed on the display. 83.456 g Information: The balance is only ever able to store one tare value.
6.2.2 Piece counting (excl. model KERN EW120-4NM) Display symbol: PCS When counting units you can either count items into or out of the container. In order to be able to count a substantial number of items, the average weight per item must be determined using a small quantity (reference units). The greater the reference unit, the greater the counting accuracy. A particularly high reference must be chosen for small or greatly varying parts.
4. Further reference units of 10, 30, 50 and 100 can be called up by repeatedly operating the key. Important: The greater the reference unit, the more accurate the unit count. Pcs M on 30 10 100 30 50 5. Place as many items to be counted on the balance as required by the set reference unit. Pcs M 6. Operate the key. The reference unit is stored. on 30 Pcs 0 I I I F 30 Now place the items to be counted in the container. The appropriate number of items will be shown on the display. 7.
6.2.2.1 Add mode This function is used to increase the counting accuracy by increasing the reference quantity. It can thereby be avoided that an inadequate reference unit is used, as this could lead to inaccurate results. When applying this function, the necessary minimum number of items is automatically ensured. Operation Display 1. Carry out item 1-5 as in chap. 6.2.2 “Parts counter“. Pcs M on 10 e.g. place 10 items on the weighing plate. 2. Operate the key.
4. Double again (see item 3) Pcs M 40 Information: Every additionally applied number of items increases the reference and improves the counting accuracy. A particularly high quantity of reference units must be chosen for small items or items with greatly varying own weight. 5. Operate the key. The reference unit is stored. Pcs M 125 Now place the items to be counted in the container. The appropriate number of items will be shown on the display Use the key to return to the desired weighing mode.
6.2.3 Percent weighing (excl. model KERN EW120-4NM) Display symbol: % Percent weighing allows the weight to be displayed as a percentage in relation to a reference weight. The displayed weight value is adopted as a fixed prescribed percent value. (Standard setting: 100%). Operation Display 1. Use the key to switch the balance on. Use the key to select unit change-over [ % ] (see chap. 6.2.1). ο 0 I I I F 0 % Information: Tare containers can also be used during percent weighing.
From now on the applied weight is shown as a percentage. 0 I I I F 85.37 % Use the key to return to the desired weighing mode. g % Pcs Information: If the “o-Err “ error message appears: the reference weight is outside the weighing range (see chap. 1 ”Technical Data“). the set key was operated during step 2 when the weight had been applied. The 100% reference is preserved until the balance is disconnected from the mains. 6.2.4 Weighing using a tolerance range (excl.
6.2.4.1 Basic settings when weighing using a tolerance range Operation 1. Use the on. key to switch the balance Display ο 0.000 g Call up the function menu: Press the key until [Func] appears, then release. Func 1 b.G. 1 The first balance mode will appear: 2. Tolerance weighing Operate the key to call up tolerance weighing mode. 2.SEL 0 (Off) 2.SEL 1 (ON) 2.SEL 0 2.SEL 1 Use the key to change the standard factory configuration. 3. Tolerance mark display Operate the key.
4. Setting the tolerance range Operate the key + The tolerance mark is displayed in all ranges. Use the 0 I I I F 0.000 g 22.L ı. 1 key to change the setting: 22.L ı. 0 Tolerance mark is only displayed above a zero point range (+5). 5. Number of tolerance points Use the key to set the tolerance mark. 23.P ı. 1 1 tolerance mark can be displayed: - too light Use the key to change the setting: 2 tolerance marks can be displayed: + TOL - 23.P ı.
6.2.4.2 Entering the limit values by weighing Important information ! Always begin by entering the lower limit value, followed by the upper limit value. Operation 1. Use the on. Display key to switch the balance ο 0.000 g Set to tolerance weighing: Press the key until [L. SEt] appears and then release. 2. The tolerance mark will flash [ The lower limit value can be set. L. SEt - ]. Place a sample for the lower (i.e. smaller) limit value on the weighing plate: Store using the key.
4. If 2 tolerance marks have been selected, the upper limit value must now be determined. H. SEt The tolerance mark is flashing [ + ], and the upper limit value can be set. Place a sample for the upper (i.e. larger) limit value on the weighing plate: M 0000 g 5. Use the key to store. The stored upper weight value is displayed briefly; entry is completed. M EW/EG-N/EWB-e-1226 158.
6.2.4.3 Entering the limit values using the keyboard Operation 1. Use the on. key to switch the balance Display ο 0.000 g Set tolerance weighing: Press the key until [L. SEt] appears and then release. 2. Flashing display is either 000.000 or the currently stored lower limit value. Press the key: The last digit in the display starts to flash. 3. Use the key to increase the numerical value of the selected digit. 4. Use the key to select the digit you wish to alter (from right to left). 5.
7. If 2 tolerance marks have been selected, the upper limit value must now be determined. Please proceed as described in item 2, starting with the last display digit. H. SEt M 000.000 g 8. Enter the upper limit value and store.
7 Functions 7.1 Access and changing of numerous functions: The balance has been set to a certain standard configuration in the factory. This configuration is marked by a ☆. The configuration can be changed as follows: Operation 1. Access to the functions. Display ο Switch on the balance: 0 I I I F 0.000 g Press the key for about 4 seconds until [FUNC] appears: Func When released the following will appear : (possible configurations are listed in chap. 7.2.2). 1 b.G. 1 2.
7.2 List of the function parameters The balance has been set to a certain standard configuration in the factory. This is marked by a ☆. Function Display Bar graph 1 b.G. Tolerance weighing (excl. EW-120-4NM) Zero alignment 2 SEL 3 A.0 Automatic shutoff after 3 min. for rechargeable battery operation (function is only available inrechargeable battery mode) 4 A.P. Display speed 5 rE. Vibratory filter 6 S.d. Interface (excl. EWB models) 7 I.F. 81 85 S.u.
Not documented 9. Ai Data-out (only selectable, if the calibration switch is not in the calibration position see Ch. 5.10) A. PrF. Enhanced log printout following adjustment (only selectable on EG models) 0 GLP 0 ☆1 1 Not documented Always use this setting. No printout possible, if the last display location is enclosed in brackets. ☆2 Printout possible, even if the last display location is enclosed in brackets.
7.2.1 Parameters when weighing with a tolerance range (excl. model KERN EW120-4NM) Settings 21. Co. to 23. P I. can only be set if the tolerance weighing function has been activated. Function Display conditions of the tolerance mark Tolerance range Display 21. 22. Co. L I. Choice ☆1 23. P I. Tolerance mark is always displayed, even if standstill check not yet indicated. 2 Tolerance mark only displayed in connection with standstill check.
7.2.2 Parameters for the serial interface (excl. EWB models) Function Output format at interface Display 7 I.F. Choice 0 ☆1 Output condition at interface 71. o.c. (Menu setting “7 I.F. [1] or [2]“ only ) 6-digit data format 7-digit data format 0 No data issued. 1 Continuous serial output. 2 Continuous serial output upon stabilised display. Output following printing of PRINT/M. Automatic output upon stable weighing value. The first value to stabilise is adopted if this is -0.00 or less.
8 Data output (excl. EWB models) The balance is supplied as standard with an interface RS 232C. 8.1 Description of the serial data output (RS 232C) The data output is placed at the rear side of the balance. It is a 5-pole standard socket. Pin description see following illustration 1- System- internal 4 - TXD 2 - System- internal 5 - GND 3 - RXD 8.
8.3 Interface description The output format, output control, transfer speed and parity bit can be set following the choice of a certain operating mode. The various possibilities are described in chap. 7.2.2 “Parameters for the serial interface “. 8.4 Data Output 8.4.1 Data Transmission Formats By selecting the corresponding function at your balance one of the two following data formats can be set: 6-digit data format (excl.
8.4.4 Units U 1, U 2 = 2 words as ASCII codes U1 (SP) C O L O D G T T T M t (SP) P U2 G T Z B T W R L L L O o % C Code 20H 47H 43H 54H 4FH 5AH 4CH 42H 4FH 54H 44H 57H 47H 52H 54H 4CH 54H 4CH 54H 4CH 4DH 4FH 74H 6FH 20H 25H 50H 43H Meaning Gramme Carat Ounze Pound Fine ounze Pennyweight Grain Tael (Hong Kong) Tael (Singapore, Malaysia) Tael (Taiwan) Momme Tola Percent Quantity Symbol g (upper right) (upper right) (lower right) mom % (excl. EW-120-4NM) Pcs (excl. EW-120-4NM) 8.4.
8.5 Data input commands 8.5.1 Command input format is made up of 4 characters, CR=0DH, LF=0AH 1 2 3 4 C1 C2 CR LF 8.5.2 External taring command C1 C2 T SP Code 54H Content 20H Tare out command 8.5.
Remarks: Control of data output through “O0~O7” commands as well as setting up weighing scale’s functions, are actions that bring about similar effects. Implementation of commands “O8 and O9" is connected with data input commands. If any command from the “O0~O9” range has been carried out, then its status will remain active until the next command is inputted. If, however, the weighing scale is switched off, then the output data control system will return to its previous setup. 8.
10 Troubleshooting The balance should be switched off for a short time following an interruption in the programme sequence and disconnected from the mains supply. It is then necessary to repeat the weighing process from the beginning. Help: Interruption Possible cause Weight display is not illuminated. The balance is not switched on. The mains supply connection has been interrupted (mains cable not plugged in/faulty). Power supply interrupted.
