Firma:                Biolog

Modell:              Microlog 1

Kommentar:      Dokumente engl.

1.0 INSTRUMENT FAMILIARITY

1.1     Analog Display - 6" meter face.

1.2     Power Button - applies power to Instrument.

1.3     Test Tube Well - holds a round, 20 mm diameter test

          tube. The recommended test tube size is 20 mm X 150 mm.

1.4     0% Transmittance Adjust - set screw for adjusting to

          0%T when meter is turned off.

1.5     100% Transmittance Adjust - knob for adjusting to 100%T

          with a blank reference test tube in the test tube well.

CALIBRATION

lf necessary, adjust set screw for full-scale 0% transmittance reading.

Turn meter on.

Insert blank refereg..ce test tube into test tube well and adjust transmittandeto 100%.

Instrument is now ready for Operation.

MEASUREMENT GUIDELINES

Avoid contaminating standards and sample solutions.

Use the same size test tubes for standards and samples. Perform a 100% transmittance adjustment for each test tube before adding a sample into it.

Test tubes are not optically uniform. Therefore, they should be oriented consistently in the light path so that the light beam passes through the saure portion of the tube.

BATTERIES

The turbidimeter uses a 9V rechargeable NiCd battery. The battery is charged whenever the plug-in power pack is supplied with power. The instrument need not be turned on for the recharger to work.

***CAUTION***
Failure to recharge the battery
could result in premature aging.

Use of the turbidimeter may continue while the battery is charging. The internal battery maintenance circuit will recharge the battery from a fully discharged state to a fully charged state in about 12 hours. It will not overcharge. No damage will result if the charger is connected indefinitely. The instrument may be stored with the charger connected.

BATTERY LIFE

A fully charged battery will operate the turbidimeter for about 8 hours. As the battery ages, the operating time may decline. End of life will usually occur alter over 1000 discharge/recharge cycles. When recharging does not result in significant operat­ing time, the battery should be replaced.

REPLACING THE BATTERY

1. Turn power Off and disconnect power supply.

2. Remove the four rubber feet, from bottom of instrument.

3. Remove black shroud.

4. Locate battery holder on inside back panel.

5. Loosen the two screws on back panel of instrument to allow the battery to slicte out of bracket.

6. Remove battery snap from battery.

7. Replace defective battery with new battery.

CAUTION: Use only a NiCd rechargeable battery. Use of a Carbon-Zinc or Alkaline battery could result in the battery rupturing and subsequently causing harm to personel or equipment.

NOTE: Properly dispose of old batteries per local regulations.

8. Place battery snap on battery.

9. Place battery in bracket and tighten screws.

10. Test instrument for proper Operation.

11. Place bleck shroud back on instrument and reattach the rubber feet.

INSTRUMENTATION THEORY

The Biolog Turbidimeter uses a light emitting diode and 590 bandpass filter, which produces a monochromatic light at 590 nm. A current is developed by the photodiode pro­portional to the amount of light received. The current is then converted to a numerical value, shown as either ab­sorbance or percent transmittance, depending on scale Chosen.

Power is applied to all circuitry by pressing the power but­ton. A power jeck on the rear panel of the instrument is used to apply external power and recharge batteries.

A precision current regulator provides a stable, adjustable current to the LED lamp. The % Transmittance knob ad­justs this current, allowing standardization to 100% T.

The silicon photodiode generates a current proportional to the light it receives, i.e., that passes through the test tube. This current is amplified and used to drive the meter move­ment.

The meter scale is calibrated in % Transmittance (linear with respect to transmitted light) and Absorbance (loga­rithmic with respect to transmitted light).

TROUBLESHOOTING GUIDE

SYMPTOM                                                 CORRECTIVE MEASURE

No response when                                     Adjust % knob clockwise; if

sample is inserted                                      still no response, make sure power switch is on, the instrument is plugged in, and/or battery is charged.

Non-linear                                                   Check all test solutions and

Standard Curves                                        standards for expiration and/or contamination. Replace suspicious solutions and recheck meter.

Recheck standard range - a narrower range may be necessary to assure linearity.

Unstable Readings                                     Make sure samples are completely stable and homogeneous. A sample that is changing or settling will result in unstable readings.

If all corrective actions fall, call your distributor for service.

SPECIFICATIONS

Wavelength               590 nm

Display                      6" analog meter

Transmission            0-100%

Absorbance               0 - 2 A

Linearity                     ± 2%

Repeatability             ± 0.5% T

Test Time                  10 - 15 seconds minimum

Operating Temp.

Range                       +15 to +35°C

Storage Temp.

Range                       +5 to +50°C

Operating Relative

Humidity                    20 to 70%

Storage Relative

Humidity                    0 to 90% non-condensing

Bandwidth                 10 nm

Wavelength Peak      ± 2 nm

Size                           41/2”H x 8"W x 7”D

Weight                       1.9 lbs (0.86 Kg)

Power                        9 V rechargeable NiCd battery or plug-in 9V, 100 mA power