3M静电测试仪说明书

3740 Wrist strap +shoe testerOperating Instructions MO 0688-0201February, 2001II. Declaration of ConformityThe 740 Wrist Strap and Shoe Tester is in conformity with the regulations of the EMC-directive 89/336/EWG. The following standards have been taken into account while designing and manufacturing the instrument: EN 60204-1/85,EN 60204-1/91, EN 61010 (Safety),EN 50082-1/92 and EN 50082-2/92.I. GeneralPersonnel grounding devices such as wrist straps and conductive footwear are the primary method to minimise charge generation on the human body. They must be able to drain this charge as rapidly as it is generated.For this reason, it is important to test wrist straps and conductive footwear on a regular basis to ensure they are functioning properly and that the test results can be recordedGround cord 4 mm studContact plate for wrist strap teste.g. - data transfer to PC, electrical door opening system, acoustic signal, etc.selection for wrist strap and shoe testshoe electrode On / Off switchRmax III. DescriptionThe 740 wrist strap and shoe tester is an electronic test instrument which is easy to operate and designed to be wall mounted. An AC/DC -transformer is supplied. The 740 switches off automatically after non-use for approximately 30minutes.The unit consists of two measurement circuits with an open circuit test voltage of 20 V for wrist strap and shoe test applications. For wrist strap and footwear testing, a minimum thresholdresistance of 750 k Ω is set internally. The desired maximum allowable resistance level can be selected separately for each measurement. If the resistance of the tested wrist strap or footwear is within the selected range, the green "o.k."-LED will illuminate. The red "<" -LED alerts theoperator that the resistance of the tested device isunder 750 k Ω. The red ">"-LED indicates that theselected maximum resistance is exceeded.The 740 can be connected to external devices such as computers (for data recording), electrical door opening systems, counter or other evaluating components.The 740 wrist strap and shoe testerconsists of:-3.5" - diskette containing instruction manual and 740 daily log sheet - Base unit-Data output connector plug-Wall mounting kit, 3M Dual Lock ™ fastening system and template-Cover for wrist strap plug-in jack -AC/DC - transformer -Ground cordAccessories:-Shoe electrodes type 741 (single electrode) or 741D (dual electrode) (to be ordered separately).IV. OperationConnect the AC/DC - transformer (DC 24-30 V,150 mA) to the 740 tester.Note: If you notice a delay in the response time of the LED illumination please connect the ground cord supplied to the ground socket of the 740.Please ensure proper earth ground connection!Switch the unit on. All LEDs will flash forapproximately 1 s to check their function. Selectthe desired upper maximum resistance level forboth the wrist strap and shoe test by using a smallscrew driver.The 741/741D shoe electrode must be connected if footwear testing is required.V. Wall MountingThe enclosed 3M Dual Lock™ fastening discsmust be screwed to the wall using the attachedtemplate approximately 1500 mm (5 feet) abovethe floor. Drill three holes of 5mm (0.2 in)diameter at marked locations. Make sure the areaon the 740 in which the Dual Lock™ fasteningstrips are placed is free of dust and dirt. Attach the3M Dual Lock™ fastening strips to the rear of the740 tester to the bottom and top in parallel; seedrawing for locations.For securing on the wall, press the 740 firmlyagainst the discs. For removal of the 740, lift thetop corners with both hands.VI. Wrist Strap TestPut the wrist band on with ground cord attachedand insert the ground cord into the wrist strapplug-in jack. Depress the metal contact plate andhold it. One of the indicator-LEDs will illuminate.An illuminated green LED indicates that the wriststrap performs within the resistance range of750kΩ to the upper selected value of 2, 5, 10 or35 MΩ. If a red "<"-LED is on, the currentlimiting resistor in the ground cord is bypassedand the cord has to be replaced. The red ">"-LEDindicates that the selected resistance range isexceeded. Check to see if the high resistance is inthe cord, the wrist band or in the contact betweenwrist band and the operator’s skin. To check theresistance of the ground cord, leave the plug endof the ground cord attached to the tester anddisconnect the snap end from the wrist band.Connect ground cord snap to the stud in the handsymbol or press it onto the contact plate anddepress the plate until one of the LEDs isilluminated.TemplateIf the green LED illuminatesnow, the ground cord can beused.If the red ">"-LED is lit,replace the ground cord.In some cases, high contact resistance between theskin and wrist band will cause the tester to show ared ">" - LED condition. This resistance may becaused by dry skin or the presence of hair in thewrist area. The use of a skin lotion isrecommended to solve this problem.If a red ">"- LED condition still exists, replace thewrist band.VII. Shoe testEither the 741/741D shoe electrode must be connected to the 740 shoe jack.a) when the 741 single shoe electrode is used:If the red ">"-LED is illuminated, clean the soles of the shoes or check shoe grounding system (heel ground or toe ground strap) and retest. If, after cleaning, the red ">"-LED remains lit, replace it by an appropriate device. If the red "<"-LED is illuminated, the minimum resistance of the shoes or shoe grounding system is under 750 k Ω.An electrical hazard to personnel may exist at the work place.b) when the 741D dual shoe electrode is used:The dual shoe electrode allows differentiation between the right and left shoe; giving the right shoe a preference in indication. This means, if both shoes or just the right one are out of range,you will get identical indications as it would be with the single shoe electrode. If just the left shoe is out of range, the corresponding red LED will flash. Consequently, in case of a steadily lit red LED, you shall clean or remove right shoe first and retest. If the right shoe is in the "ok"-range then, you will obtain information aboutperformance of the left shoe and you can react accordingly.The shoe test does not influence the wrist strap test, therefore the shoes can be tested while the wrist strap is still connected to the 740 or the wrist strap can be tested while the operator is standing on the 741 shoe electrode. Both metal plates shall not be pressed at the same time.Switch the 740 on. Stand on the applied shoe electrode. If you are using shoe straps with a 1M Ω - resistor on both feet to be tested with the 741 shoe electrode, you have to test the straps one after the other, to avoid a red "too low" -indication. Care must be taken not to put the non-tested foot on ESD - protective flooring to avoid a bypass to ground. Depress the metal contact plate for shoe test until one of the indicator - LEDs lights up. The green LED indicates that theresistance of the person through the footwear is in the range between 750 k Ω and the desired upper maximum level (10, 35, 50 or 100 M Ω).VIII. Data Output ConnectorIf you are going to use the data output connector you must follow a test sequence. It must be wrist strap test first and then the shoe test. If this sequence is not strictly kept, the output at the pins described on page 7 will be mixed up .The 740 will provide digital signals (high/low) while testing the personnel grounding devices. These digital signals can be used for data recording (Example 1) and authorisation control equipment such as electrical door opening systems (Example 2). The output of the 740 will give you permanently +5 V at pin 3 and DC-return at pin 6. The remaining pins 1, 2, 4 and 5 (open collector) will be high(max.+30 V/20 mA have to be provided externally) or low (DC-return) while pressing on the contact plates either for wrist strap or shoe tests. The chart on page 7 shows all of the possible test results and the corresponding output levels.Example 1: Output connection for use with a computer Example 2: Output connection for use with a controlling deviceComputer input Computer groundData output connector pin status when testing wrist strap/shoeThe sequence for testing must be wrist strap test first and then the shoe test.Shaded pin indicators will read "hi" if the sequence is reversed or only the shoe tests are performed.Data Output Connectorpin 1, 2, 4, 5-high or low pin 3-+5 V pin 6-DC-returnIX. SpecificationsDimension of base unit :138 mm x 190 mm x 53 mm (5.25 x 7.5 x 2) inches Weight :450 g (15.75 oz)Power supply :external AC/DC - transformer,DC 24-30 V/150 mAAccuracy :± 10% of 2, 5, 10, 35 and 50 M Ω-ranges ± 20% of 100 M Ω-range Output :open collector at pin 1,2, 4, 5(max. +30 V/20 mA)DC-return at pin 6, +5 V at pin 3Measurement voltage :DC (20±1) V (open circuit)750 k ΩᕡᕣᕢX. Calibration ProcedureThe following procedure can be used to determine if the 740 operates within its specifications.Please note: The tester has no adjustable components.Equipment needed:1.Resistors750 k Ω - 120 M Ω, tolerance ± 1%2. 2 leadsas required to connect the reference resistora) calibration of wrist strap test circuit:Connect the reference resistor to the 740 as shown in the figure below. Switch the 740 unit on. Select the 2 M Ω-range and use the reference resistors as indicated in the test table and press contact plate A.b) calibration of shoe test circuits:The 740 Tester can either operate with the single or dual shoe electrode. They are identified by the wiring in the 3-pin plug according to DIN 41 524,type HIRSCHMANN MAS 3100, that connects the shoe electrode to the 740. For the single shoe electrode, the cord is connected to pin 1 while pins 2 and 3 are shunted and grounded.The dual shoe electrode uses the same plug but has got the following connections:pin 1: right shoe electrode pin 2: openpin 3: left shoe electrode.Reference Resistance LED -resistor range settings Indication *750 k Ω 2 M Ω - rangeRed 900 k ΩGreen 1.8 M ΩGreen >2.2 M ΩRed 4.5 M Ω 5 M Ω - range Green >5.5 M ΩRed 9.0 M Ω10 M Ω - range Green >11.0 M ΩRed 31.5 M Ω35 M Ω - rangeGreen >38.5 M ΩRed*This example is used aboveThe LEDs will indicate as shown below if the 740performs within specifications. Repeat this procedure for 5, 10 and 35 M Ω-ranges.11.1 MΩII) calibration of the dual shoe test circuits: The 740 Tester measures the resistance of both shoes almost at the same time. The test result for the circuit of the right shoe has got priority. The calibration can be either performed with two reference resistors for both circuits to be checked at the same time or -corresponding to the single shoe test - with one reference resistor for one circuit to be checked and an appropriate bridge resistor (1MΩ e.g.) for the other circuit. For completion of calibration, the test has to be repeated with connections of the resistors vice versa. Follow the instructions for the single electrode calibration test accordingly.For the operation with two reference resistors proceed as follows: Connect one reference resistor between contact 1 of the socket and the stud and the other one between contacts 2 and 3. Select the 10 MΩ-range and set the reference resistors as indicated in the test table and press contactplate B. The LEDs shall light as shown below. Repeat this procedure for 35, 50 and 100 MΩ-ranges.Right shoe Left shoeelectrode electrodecircuit circuit SignalOK OK green steadily high OK>red steadilylow OK<red steadilyOK high>red flashingOK low<red flashing high low>red steadilylow high<red steadily high high>red steadilylow low<red steadilyI) calibration of the single shoe test circuit: Connect a reference resistor to the 740 between contact 1 of the socket and the stud as shown below. Contacts 2 and 3 of the socket shall be bridged via an appropriate resistor (1MΩ e.g.) Select the 10 MΩ-range and set the reference resistors as indicated in the test table and press contact plate B.The LEDs shall light as shown below. Repeat this procedure for 35, 50 and 100MΩ-ranges.Shoe electrodecircuit SignalOK green steadilyhigh>red steadilylow<red steadily3M 740 Wrist Strap + Shoe Tester Logbook11 / 11MO 0688-0201Distributed by:SJM Eurostat UK Ltd.Countess Avenue Stanley Green Trading Estate Cheadle Hulme, Cheshire SK8 6QS United Kingdom Tel: +44 (0) 161 485 5002Fax: +44 (0) 161 485 46783M France Electronic Handling & Protection Boulevard de l ’Oise 95006 Cergy Pontoise Cedex T él.: +33 (0) 130316809Fax: +33 (0) 130316181SA au capital de 52500000francs RC Pontoise b 542078555, ape 246 C 3Magnab Eurostat Skvasta Industriby 16BN 61192 Nyk öping Sweden Tel: +46 (0) 155 20 26 80Fax: +46 (0) 155 26 98 34Important notice to purchaser "Warranty-3M expressly warrants that for a period of twelve (12) months from the date of purchase,3M Static Control Products will be free of defects in materials (parts) and workmanship (labor).Defects occurring during the warranty period will be repaired or products will be replaced at 3M ’s option and expense, if 3M receives notice during the warranty period. Defective products must be returned to 3M with proof of purchase date.Warranty exclusions: the foregoing express warranty is made in lieu of all other productwarranties, express and implied, including fitness and merchantability. The express warranty will not apply to defects or damage due to accidents,neglect, misuse, alterations, operator error, or failure to properly maintain, clean, or repair products.Limit of liability-in no event will 3M or seller be responsible or liable for special, incidental, orconsequential losses or damages, whether based in tort or contract. Fulfillment of 3M ’s warranty obligations will be customer ’s exclusive remedy and 3M ’s and seller ’s limit of liability for any breach of warrant or otherwise."。