TECHNICAL BULLETIN TB-3019 Dual-Wire Workstation Continuous Monitor Installation, Operation, and Maintenance Made in America Figure 2. Dual Wire - Dual Operator Programmable Monitor rear view Figure 1. Desco 19665 Dual Wire - Dual Operator Programmable Monitor Packaging Description 1 Dual Wire - Dual Operator Programmable Monitor Continuous monitors pay for themselves, by improving quality, 1 Snap Kit productivity, and eliminating daily wrist strap testing and test 1 Power Adapter result logging. Per ESD-S1.1 paragraph 6.1.3 Frequency of 2 Operator Ground Cables (black and white) Functional Testing, “The wrist strap system should be tested 2 Monitor-to-Mat Ground Cords (black and white) daily to ensure proper electrical value. Daily testing may be 1 Monitor Ground Cord (green with yellow stripe) omitted if constant monitoring is used.” 2 Mat Ground Cords (green with yellow stripe) Per ESD Handbook TR20.20 paragraph 5.3.2.4.4, “Typical test Installation programs recommend that wrist straps that are used daily should be tested daily. However, if the products that are being A. Determine the mounting location of the monitor. The front produced are of such value that knowledge of a continuous, panel should be visible to a supervisor. reliable ground is needed, and then continuous monitoring B. Determine the mounting location of the operator remotes. should be considered or even required.” The white remote is for operator #1 and the black remote is The Desco Dual Wire - Dual Operator Programmable Monitor for operator #2. Make sure that each remote is located so can maintain two work surfaces and two operators at ground that the remote leads reach the monitor but are convenient potential to virtually eliminate the risk of ESD damage. The for the operator. highly visible LED display and audible alarm makes it easy to C. Attach the operator remotes to the bench or other surface monitor the status of the work surfaces and operators. The using the provided screws. Dual-Wire Dual-Operator Programmable Monitor uses Desco’s patented* dual resistive loop technology. No other method is as D. Attach the tinned wire ends of the mat wires to the direct and reliable. Both work surfaces, and individual operator appropriate screw terminal connection on the rear of the resistance limits, can be programmed and re-configured as unit. (See Figure 2). The white wire is for operator #1 and required. If the ground potential of either work surface or the black wire is for operator #2. operator is lost the, monitor immediately alarms (both audible and visual). The monitor is unaffected by capacitance E. If not already done, attach the work surface to workstation variations associated with personnel and environmental common point ground using the pictured ground wires. For conditions. mats, attach the grounding point snaps at the ends of the ground monitor cords to the grounding point snaps on the The Dual Wire - Dual Operator Programmable Monitor work surface. These ground monitor cords are used for features: sensing whether or not the unit is properly grounded. Refer • Monitoring of two operators independently. to figure 3 for snap-plate fitting diagram and for laminates or • Monitoring of two ground connections (work surfaces) ther hard surfaces with a buried conductive layer. independently. • Fully independent alarming conditions: audible and visual. F. Attach the tinned wire end of the black ground-reference • Independent LED status lights for each operator and each wire to the center position of the screw terminal block on ground connection (work surface.) the rear of the unit. Attach the ring terminal end to an • Two independent operator wrist strap ground point remotes alternate ground point. It is important that this ground wire is with 10’ cables. attached to a separate ground point other than the work surface ground cords from the previous step to ensure proper independent monitoring. The faceplate screw of a grounded AC wall outlet may provide a convenient *U.S. Patents 6,052,053 and 6,205,408 connection point. DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 • (909) 627-8178 • Fax (909) 627-7449 DESCO EAST - 90 Hudson Road, Canton, MA 02021-1407 • (781) 821-8370 • Fax (781) 575-0172 • Web Site: Desco.com © 2007 DESCO INDUSTRIES INC. TB-3019 October 2007 Page 1 of 3 Employee Owned Operation Wrist Strap Connections Once all the connections described above have been made and the unit has been powered up, the unit is ready for opera- tion. Install operator wrist straps and ground wires. Dual snaps on the operator ground wires attach to the wristband snaps and the mono plug on the other end inserts into the operator remote as illustrated in Figure 5. The operator's monitoring is in "STANDBY" mode until the operator's ground wire is plugged into the remote jack for that station. Figure 3. Installing the Dual Wire - Dual Operator Programmable Monitor G. Route the work surface monitor wires from the back of the monitor unit, to the snaps/bolts attached to the grounded Figure 5. Connecting wrist straps to the operator remote surfaces. Attach the white ground wire to the operator #1 work surface and the black ground wire to the operator #2 NOTE: The operator remote has two jacks. One is a 3.5 mm work surface. mono jack for use with a dual wrist strap. A dual operator H. Route the operator remote wires to the monitoring unit and ground wire plugged into this jack will be monitored. The other insert the modular plugs into the appropriate jacks on the jack is a grounded banana jack for use with a single conductor rear of the unit. (See Figure 2) operator ground wire. This is a grounded guest hook-up that is not monitored. Mat Grounding It is recommended to connect the mat wire (10mm snap) from Status Indicators the monitor and the mat ground wire (10mm snap) to two The audible alarm for Operator 1 and Ground 1 is continuous. separate points on the bench mat as shown in Figure 4. The audible alarm for Operator 2 and Ground 2 is a repetitive beep. If a fault condition exists for both operators and/or both grounds, the alarm will sound continuously. The alarm volume may be adjusted with the potentiometer on the rear of the unit (see Figure 2). Figure 4. Grounding the work surface mats I. Plug the DC power supply plug into the power jack in the rear of the unit. Route the wire from the supply to a nearby AC outlet and plug the power adapter into the outlet. Make sure the voltage and frequency match those listed on the AC adapter. The monitor should now be powered. Figure 6. LED features and components DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 • (909) 627-8178 • Fax (909) 627-7449 DESCO EAST - 90 Hudson Road, Canton, MA 02021-1407 • (781) 821-8370 • Fax (781) 575-0172 • Web Site: Desco.com © 2007 DESCO INDUSTRIES INC. TB-3019 Page 2 of 3 Employee Owned The monitor provides status indicators for the following conditions: • Standby - The operator is not plugged into the remote. This condition is indicated by a flashing yellow LED in the operator section of the display. • Operator Fail High - The operator's series resistance is greater than the upper resistance limit. This condition is indicated by the red LED in the Operator section of the display along with an audible alarm • Operator Fail Low - The operator's series resistance is less than 1.9Meg Ohm. This condition is indicated by the flashing yellow LED in the Operator section of the display. • Operator Pass - The operator's series resistance is within the range of 1.9Meg Ohm to the upper resistance limit. This Dip Switches condition is indicated by the green LED in the Operator section Function Down Up of the display. • Ground Fail High - The resistance from the mat connection to ground is greater than 3.5Meg Ohm. This condition is Switch 1 Input Voltage 8v 5v indicated by the red LED in the Ground section of the display as well as an audible alarm. Switch 2 5v 8v • Ground Pass - The resistance from the mat connection to Wrist Strap ground is less than 3.5Meg Ohm. This condition is indicated by the green LED in the Ground section of the display. Switch 3 High limit 35m 10m The resistance values quoted above are the Factory Defaults. supply connection plug is accessible to the user and there is These numbers will vary depending on the configuration. no safety insulation inside the monitor. Therefore, the insulation of the power supply is critical. Changing the Test Voltage • Rated Power consumption: 3.6VA. The monitor can be set for a test voltage of either +5V or +8V. Reducing the test voltage will result in a lower finger-tip voltage Environmental Conditions on the operator. To change the test voltage you must set two • Suitable for indoor use only at altitudes not exceeding 6500 switches inside the unit. ft. (2 km) The unit is set at the factory at 8 volts. NOTE: If the unit • Maximum relative humidity of 80% up to 88°F (31°C) decreasing linearly to 50% @104°F (40°C) changed to a different voltage, it must be recalibrated. • Pollution degree 2 per IEC 644 Remove the four case screws and open the monitor’s case. • Temperature range of 41°F (5°C) to 104°F (40°C) BE SURE TO OBSERVE ESD PRECAUTIONS, AS THERE ARE ESD SENSITIVE DEVICES INSIDE THE CASE. Refer to Limited Warranty Figure 7 for setting the test voltage to +5V and +8V. Desco expressly warrants that for a period of one (1) year from the date of purchase, Desco Monitors will be free of defects in material (parts) and Calibration workmanship (labor). Within the warranty period, a unit will be tested, repaired, or replaced at our option, free of charge. Call our Customer Service Department at The Desco EMIT 50524 Dual-Wire Monitor Limit Comparator 909-627-8178 for a Return Material Authorization (RMA) and proper shipping instructions and address. Include a copy of your original packing slip, invoice, or may be used to check the test ranges of the Dual Wire - Dual other proof of purchase date. Any unit under warranty should be shipped prepaid to Operator Monitor. See Desco EMIT TB-6542 for instructions. the Desco factory. Warranty repairs will take approximately two weeks. Specifications If your unit is out of warranty, call our Customer Service Department at 909-627- 8178 for a Return Material Authorization (RMA) and proper shipping instructions • Two user selectable resistance levels of 10 Meg ohms or 35 and address. Desco will quote repair charges necessary to bring your unit up to factory standards. Meg ohms. • Two user selectable test voltage settings of +5V or +8V. Warranty Exclusions • SCCN compatible data output. THE FOREGOING EXPRESS WARRANTY IS MADE IN LIEU OF ALL OTHER PRODUCT WARRANTIES, EXPRESSED AND IMPLIED, INCLUDING • Stainless Steel housing. MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE WHICH • Size: 4.3" W x 4.4" D x 1.8" H ARE SPECIFICALLY DISCLAIMED. The express warranty will not apply to defects • Plug-in power supply: 110 VAC/60Hz input, 12VDC/500mA or damage due to accidents, neglect, misuse, alterations, operator error, or failure output. 2.5mm connector - center positive. Any alternate to properly maintain, clean or repair products. transformer must comply with the Safety Extra Low Voltage Limit of Liability (SELV) insulation requirements. In no event will Desco or any seller be responsible or liable for any injury, loss or • Important: This appliance has a metal casing but the earth damage, direct or consequential, arising out of the use of or the inability to use the product. Before using, users shall determine the suitability of the product for their connection is only used for operational purposes. It is intended use, and users assume all risk and liability whatsoever in connection considered to be class I and tested as class II. The power therewith. DESCO WEST - 3651 Walnut Avenue, Chino, CA 91710 • (909) 627-8178 • Fax (909) 627-7449 DESCO EAST - 90 Hudson Road, Canton, MA 02021-1407 • (781) 821-8370 • Fax (781) 575-0172 • Web Site: Desco.com © 2007 DESCO INDUSTRIES INC. TB-3019 Page 3 of 3 Employee Owned