MANUAL BMS SPEC5000 Spectrophotometer

Transcription

1 MANUAL BMS SPEC5000 Spectrophotometer BMS Art. Nr

2 1 PRINCIPLE, APPLICATION AND CHARACTERISTICS 1.1 Principle The SPEC5000 spectrophotometer is a single beam spectrophotometer with a basic structure and good properties. It is designed for quantitative and qualitative analysis of various samples, based on optical absorption of substances and the principle of comparative measurement. Setting the transmittance of a standard sample at 100%, the transmittance of a measuring sample, at a certain concentration range, will relate to the standard sample according to: A = log 1/T = KCL T = I / I0 Where : A : Absorbance T : Transmittance relative to the standard sample I : Intensity of the light that is detected through the measuring sample I0 : Intensity of the light that is detected through the standard sample K : Extinction coefficient of the sample L : Length of the optical path in the sample C : Concentration 1.2 Application Photo spectrometry is widely used for quantitative and qualitative analysis of various substances in biochemistry, petrochemistry, environmental monitoring, education, medical examination, etcetera. 1.3 Main description 1. Wide spectral range (335 ~ 1000 nm). The wavelength and measurement reading are numerically displayed 2. Automatic replacement of 0 and 100%T 3. Errorless T-A transition 4. Functions for the setting of concentration and concentration factor 5. Completely obscured sample chamber. 6. RS232C Connector for connection to a personal computer 2 SPECIFICATIONS AND STANDARD ACCESSORIES Optical system : C-T mono chromator, 1200 lines/mm holographic grating Wavelength range : 335 ~ 1000 nm Light source : Halogen Tungsten Lamp (20W / 12) Wavelength accuracy : ± 2 nm Wavelength repeatability : 1 nm Photometric accuracy : ± 1,0 % (T) Photometric repeatability : 0,3 % (T) Spectral bandwidth : 10 nm Stray light : 0,2 % (T) (360 nm, NaNO2) Display : T 0 ~ 100,9 % A -0,3 ~ 2,5 2

3 Power Power consumption Dimensions Net weight F 1 ~ 9999 C 0 ~ 9999 : 220 ± 10 %, 50 Hz (On request 110 ± 10 %, 60 Hz) : 50W : 385 x 310 x 190 mm : 5,5 Kg Standard configuration : Item Amount Spectrophotometer 1 Square colorimetric 2 1 cm long colorimetric frame 2 Colorimetric frame with Pr-Nd glass 1 Power cord 1 Manual 1 RS232C cable 1 Software 1 Fuse (1 A) 2 Optional accessories and spare parts : Fuse (1 A) Power lamp with adjustable holder 1 cm, 2 cm, 3 cm colorimetric sample 1 cm, 2 cm, 3 cm colorimetric frame 3 NAME AND FUNCTION OF COMPONENTS AND OPERATION KEYS 1 MODE : Select operating mode. By pressing this key the indication for TRANSMITTANCE, ABSORBANCE, FACTOR and CONCENTRATION will light respectively. This indicates the current operating mode. 2 FUNC : Function key. By pressing this key with the indication light on FACTOR, it changes the settings of the FACTOR data. By pressing this key with the indication light on CONCENTRATION, it changes the settings of the CONCENTRATION data. Under all four operating modes the readings in the display can be transferred to a personal computer using the RS232 port 3 100%ADJ : 100% Adjustment key. Press this key once with the indication light on TRANSMITTANCE to automatically adjust 100% (T) By pressing this key once with the indication light on ABSORBANCE the value will be set at 0,000. By pressing this key with the indication light on FACTOR, it decreases the FACTOR value. By pressing this key with the indication light on CONCENTRATION, it decreases the CONCENTRATION value. 4 0%ADJ : 0% Adjustment key. Press this key once with the indication light on TRANSMITTANCE to adjust the 0% (T) value. With the indication light on ABSORBANCE this key has no function. By pressing this key with the indication light on FACTOR, it increases the FACTOR value. By pressing this key with the indication light on CONCENTRATION, it increases the CONCENTRATION value. 3

4 5 CONCENTRATION indication light : Display shows test data or settings value 6 FACTOR indication light : Display shows concentration factor value 7 ABSORBANCE indication light : Display shows absorbance value 8 TRANSMITTANCE indication light : Display shows transmittance factor value 9 LED Display : Displays the testing data and overflow information 10 LED Display : Displays the current wavelength 11 Sample chamber : Chamber for the colorimetric frame 12 Wavelength knob : Knob for the adjustment of the wavelength 13 RS323C port : Port for PC connection using the RS323C interface cable 14 fine-tuning : Fine-tuning for the correct display of the wavelength 15 Power connector : Power connector for the connection of the power cord 16 Fuse holder : Holder for the 1 A fuse 17 Power switch : Switch to turn the system power on or off

5 4 INSTALLATION 4.1 Placement The instrument is suitable for placement in an analysis lab and connection to a computer. The operating conditions are as follows: * Temperature : 5 ~ 35 C * Humidity : < 85 % * Main power : 220 ± 10 %, 50 Hz (On request 110 ± 10 %, 60 Hz) * Avoid exposure to sunlight, high temperatures, humidity, dust and vibrations. * Clean the surface of the instrument gently with a humid cloth. Do NOT use ethanol, ether, acetone, etcetera. Transport the instrument in the original box and use it in a suitable operating environment. 4.2 Unpacking Before opening check if the box is in good condition, if the package is damaged or broken, contact the transporters insurance Unseal the box by removing the adhesive tape (Keep the box for future transportation). Check the previous mentioned standard configuration, if wrong, please contact the district agent or company. 4.3 Installation Remove any adhesive tape and clean the surface. Place the spectrophotometer on a steady desk, at least 10 cm from the wall. Connect the power cord and turn the power on. 5 OPERATION 5.1 Basic operation of the instrument Pre-heating Turn the spectrophotometer on for about 30 minutes in order to warm up the instrument. If the pre-heating is less than 30 minutes pay attention to the adjustment of 0 % (T) and 100 % (T) during measuring Adjust 0 Objective : Adjust the two extremes of the reading range (0 % (T) and 100 % (T)), also adjust 100 % (T) for the correct test status. When : After the pre-heating period, after wavelength testing, after a long test period and before a precision test. Operation : Check if the TRANSMITTANCE indication is lighted, if not, press the MODE key to change to the TRANSMITTANCE operating mode. Close the sample chamber without any sample in the chamber and press the 0%ADJ key to adjust 0 automatically. 0.0 is now shown on the numerical display Adjust 100 % (T) Objective : Adjust the two extremes of the reading range and also adjust 0 % (T) for the correct test status. When : After the pre-heating period, after wavelength testing, after a long test 5

6 Operation Attention Period and before a precision test. : Put the empty colorimetric cell into its frame and insert it into the sample chamber (The instrument will open the optical gate automatically) and close the sample chamber. Press the 100 % (T) key and 100 % (T) will be adjusted automatically. : The automatic gain system in the instrument will affect the 0 % (T) after 100 % (T) adjustment, please check 0 % (T). If changed, adjust 0 % (T) repeatedly Adjust wavelength It is convenient to adjust the current testing wavelength with the wavelength knob (12). For accurate wavelength display, the following steps must be taken: 1. Close the sample chamber and press the MODE key until the TRANSMITTANCE indication is lighted. 2. Turn the wavelength knob until 800 nm is displayed on the LED display. Insert the empty colorimetric frame into the sample chamber and set 0 % (T) and 100 % (T) according to steps and Then remove the empty colorimetric frame, insert a colorimetric frame with Pr-Nd glass and close the sample chamber. Now shift the wavelength with 1 nm steps until 807 nm is displayed. Use air as a reference, test each transmittance value at different wavelengths and find out the wavelength which corresponds to the minimum transmittance value. 3. If the wavelength value is 807 nm ± 2 nm, which means it lies between 805 nm and 809 nm, then the value displayed is accurate and doesn t need any adjustments. If the wavelength differences more than ± 2 nm, the accuracy needs to be adjusted following the next step. 4. Insert a screwdriver into the fine-tuning hole (14). Turn the screwdriver clockwise or counter-clockwise to change the wavelength value until 807 nm is displayed. Attention : The optical filter is changed by a mechanical linkage when the fine-tuning knob is turning between 380 nm and 560 nm, this means that when the knob is turning between nm and nm, there is a slight frictional sound, which is normal Change sample chamber The entirely obscured sample chamber insures that the instrument has low stray light. Two types of sample chambers are suitable for the colorimetric 1 cm, 2 cm, 3 cm light length. They can be interchanged if required. The interchanging can be achieved as follows: Open the sample chamber cover, insert a screwdriver inclined at a 45 angle into the hole at 10 mm from the top of the chamber. Remove the chamber fixation screw and pull out the entire chamber in vertical direction. Install the other sample chamber by following the steps in reverse Set sample 1. Select the colorimetric frame for testing 2. Place the sample cell in the colorimetric frame 3. Open the sample chamber and insert the colorimetric frame into the chamber, the optical gate will open automatically. Close the sample chamber Change operating mode There are four types of operating modes on the SPEC5000: 6

7 1. TRANSMITTANCE : Reading of the transmittance 2. ABSORBANCE : Reading of the absorbance 3. FACTOR : Setting of the concentration factor 4. CONCENTRATION : Setting and reading of the concentration Switching between these four modes can be done by pressing the MODE key. When the power is turned on, the operating mode indicator will show TRANSMITTANCE. At that time the instrument is preparing to measure the transmittance of a sample, and the numerical display shows the transmittance value. Press the MODE key continuously and the operating mode indicator will show ABSORBANCE, FACTOR, CONCENTRATION and TRANSMITTANCE sequentially while the displays show the current settings and readings Setting of concentration factor and concentration 1. Setting of concentration factor: When the operating mode indicator indicates FACTOR, hold the MODE key until the right part of the data in the display is blinking, which means the setting-mode is enabled. Press the FUNC key continuously as each segment will blink in turn from right to left. The value of each segment can be changed by pressing the UP or DOWN key (0%ADJ and 100%ADJ) when blinking. When the correct value for the four segments is set, press the MODE key again and a 4-bit concentration factor value will be shown on the numerical display. 2. Setting the concentration: When the operating mode indicator indicates CONCENTRATION, hold the MODE key until the right part of the data in the display is blinking, which means the setting-mode is enabled. Just like in the operation steps to set the concentration factor, press the FUNC key to select the desired data segment, then press UP or DOWN to select the correct value. Press MODE again and the concentration value will be shown on the numerical display RS232C cable for the spectrophotometer The instrument can be connected to a personal computer using the RS232C interface. The interface output is defined as follows: Baud rate : 9600 bps Data bit : 8 bit Stop bit : 1 bit 5.2 Application and operation Measuring the transmission of a transparent material 0 Pre-heating Set wavelength Switch to transmission mode Adjust 0 % (T) Set blank colorimetric frame Adjust 100 % (T)

8 6 Set sample for measuring Read data Measuring a transmission curve of a transparent material Following the steps of 5.2.1, measure the sample repeatedly in de required wavelength interval at different wavelengths. Write the different transmittance values on paper. This data will form a transmission curve of the tested sample. A different way to obtain a transmission curve is to connect the instrument to a computer using the RS232C interface and the transmission curve can be displayed on the PC or printed measuring the absorbance of a transparent fluid 0 Pre-heating Set wavelength Adjust 0 % (T) and 100 % (T) 5.1.2/5 3 Switch to absorbance mode Set sample for measuring Read data Measuring the concentration using the standard curve method 0 Pre-heating Take standard sample with known concentration Mix the sample fluid and the comparative fluid according to analytical regulations Set wavelength, adjust 0 % (T), set blank, adjust 100 % (T), Switch to ABSORBANCE mode Test the absorbance of each standard fluid Draw the C-A curve by hand with the concentration data of each standard fluid and the data of the corresponding absorbance or plot the curve using the PC and the RS232C interface 8

9 6 Test the absorbance of the measuring sample Read the sample concentration from the curve Application of the concentration When the sample is stable and its standard curve is nearly zero, it is not necessary for the user to test the sample quantitatively using the complex standard curve method. The method of direct concentration reading can be used. The standard concentration of the sample is set at 2/3 of the entire quantificational concentration range which the user desires to measure. The operation steps are as follows: 0 Pre-heating Set absorbance of the standard sample Switch to concentration mode Set the concentration value for a standard content or its 10 n zoom 4 Set fluid sample for measuring The content value of the sample can be directly read on the display (or display X 10 n zoom) Application of the concentration factor Set the FACTOR mode following the first three steps of 5.2.5, the concentration factor of a standard sample will be shown on the display. Record this value as it is needed to get the concentration value of a measured sample using the method of direct concentration reading. You don t need to measure the concentration factor of a standard sample next time you need to measure the same sample. The operation steps are as follows: 0 Pre-heating Set wavelength, adjust 0 % (T), set blank, adjust 100 % (T) Switch to Factor mode Set the concentration factor as measured and recorded 4 Set fluid sample for measuring The content value of the sample can be directly read on the display (or display X 10 n zoom) 9

10 6 GENERAL MAINTENANCE AND TROUBLESHOOTING 6.1 Periodic maintenance Precautions at use 1. The instrument s environment for daily use should accord with chapter Clean the surface of the instrument gently with a humid cloth. Do NOT use ethanol, ether, acetone, etcetera, but use neutral detergent if necessary. Cover the instrument with the dust cover when not in use. 3. The colorimetric should be washed with petroleum-ether, can be cleaned with soft paper and should be put back in the colorimetric box after every use. 4. The effective wavelength measuring range is limited by a frame. Avoid using force when turning the circular knob near the wavelength of 335 nm and 1000 nm, which might cause the frame to break. (Though the wavelength can be set at a total range of 332 nm up to 1003 nm) Opening the cover for inspection The instrument s cover should be opened in order to check the frame, optical system and electrical circuit or to change the light source. The operation steps are as follows: 1. Switch of the power and disconnect the power cord. 2. Take out the sample chamber as shown in Remove the two screws which are located at the side of the adjustment knob and vertically remove the knob. 4. Remove the two M3 screws at the front of the instrument s base and lift the cover of the instrument. Every section of the instrument can be checked now Changing the light source In the instrument a long-life pre-regulated light source is used. It can be replaced easily when defective. The pre-regulated light source can be changed as follows: 1. Open the instrument s cover as shown in Remove the old light source: pull out the power cord at the mono-chromator cover, remove the screws at the light source holder and take out the light source. 3. Mount the new light source following in contrary the steps of (2). 4. Connect the power cord of the new light source at the mono-chromator cover. 5. Switch the main power on and select 560 nm as wavelength. Remove the observation cover and inspect if the light is aimed at the incident slit. If not, release the light source s fixation screws and move the light source sideways until the light is aimed at the incident slit. Now tighten the fixation screws. 6.2 Checking of the spectrophotometer s functioning Check and adjust the following to improve the eligibility of the instruments before they leave the factory or after being repaired Checking the wavelength range 1. Turn the spectrophotometer on and let it pre-heat for about 30 minutes, then press MODE to select the TRANSMITTANCE operating mode. 2. Turn the wavelength adjustment knob from the long wavelength position to the short wavelength position, the display should show every wavelength at a range of 335 nm to 1000 nm. 3. Weather at a short or long wavelength, press the 100%ADJ key to adjust 100 % (T), the numerical display shows Without the colorimetric frame, 10

11 press 0%ADJ to adjust 0 % (T), now the numerical display shows Checking the photometric repeatability 1. Set the wavelength at 560 nm. 2. Place the sample (Generally a neutral filter) which has an even absorbance with a transmittance of around 40%. Check the display readings three times, the maximum difference should be equal or less 0.3% Checking the wavelength repeatability 1. Set the operating mode to TRANSMITTANCE. 2. Adjust 0 % (T) at the background state, then insert a blank colorimetric frame in the sample holder and adjust 100 % (T). Insert a colorimetric frame with Pr-Nd glass in the sample holder and test the transmittance at a wavelength range of 800 nm to 815 nm and record the wavelength when the minimum transmittance is observed. 3. Repeat step 2 several times (At least three times) and every time write down the wavelengths. The difference in wavelengths should be equal or less 1 nm. Symptom Cause Check & Solution The instrument does not respond to the power switch 1. Power cord is not connected 2. Power fuse is blown 2. Change the fuse Numerical display readings are unstable when measuring No signal when measuring Can not adjust 100 % (T) Can not adjust 0 % (T) Test data is abnormal 1. The pre-heating time of the instrument is insufficient 2. Power supply is unstable 3. External vibrations are excessive 4. Electric circuit is defective 1. Light source is not switched on 2. Optical gate is closed 3. There is no signal output from the detector 1. The light energy is insufficient 2. Colorimetric frame is incorrectly inserted and the optical gate is closed 1. A blank colorimetric frame is inserted in the sample chamber and the optical gate is opened 1. The sample is not processed correctly 2. Colorimetric sample is incomparable 3. The actual wavelength and the displayed one differ greatly. 1. Check if the power supply is normal, check if the cable is connected correctly, check if the power switch is turned on 1. Time of pre-heating should be > 30 min. 2. Power supply should not vary more than 10% (110 / 220) 3. Change environment to comply to the chapter 4.1 requirements 4. Replace the defective electric circuit 1. Lamp is broken, change lamp unit (6.1.3) 2. Check if the optical gate can be opened 3. Input or output connector from the detector has no contact with the jack, reinsert it. If the detector is broken contact our companies service department 1. Check if the light is focused on the slit. If not see to readjust it 2. Insert the colorimetric frame correctly 1. Take out the colorimetric frame and the optical gate will close automatically. Close the sample chamber 1. Process the sample correctly 2. Deduct comparative error 3. Adjust the wavelength according to

12 Numerical display shows OER 1. The operating wavelength is switched directly from short to long while measuring 2. The sample s transmittance is over the instrument s dynamic range using the ABSORBANCE mode 1. Adjust 100 % (T) first by inserting the test sample when the wavelength is changed, then measure the sample again 2. Limit the samples to samples within the instrument s dynamic range 12