Summary of 724
Page 1
3 model 724 work station monitor instructions.
Page 2: Index
2 index section page safety information..................................................................................................3 1. Theory of operation ......................................................................................4 2. Installation of 3m™ model 724 monitor with work...
Page 3: Safety Information
3 safety information intended use the 3m ™ model 724 work station monitor is designed to monitor the operation of two wrist strap grounding systems and two work surfaces. This product has been designed and tested for use with 3m ™ dual conductor wrist straps and 3m work surfaces grounding systems. F...
Page 4: Section 1.
4 section 1. Theory of operation the 3m model 724 work station monitor (fig. 1) is designed to monitor the operation of the wrist strap grounding systems of two operators. To accomplish this, it uses a dc current source to measure a loop electrical resistance. The system uses a special wrist band an...
Page 5: Operator Monitoring -
5 the model 724 monitor allows for the selection of test voltages (9v or 16v) and resistance limits (10 megohms or 35 megohms). The additional ranges have been added to accommodate global electrical static discharge requirements. Selection of the operating parameters are left up to the user’s discre...
Page 6: Voltage On Operator
6 voltage on operator when connected to the model 724 monitor there is a concern about the voltage that is applied to an operator while they are connected to a monitor. Some of today’s electronic components are extremely sensitive to electrostatic discharge from a person (less than 10 volts). The fo...
Page 7: Audible Alarm Tones
7 audible alarm tones for wrist strap malfunctions the model 724 monitor indicates a different tone for each operator-a continuous tone for #1 operator and a fast chirping beep for #2 operator. The volume of the wrist strap alarm is adjusted by selection of the internal dip switch #1. For work surfa...
Page 8: Section 2.
8 section 2. Installation of 3m ™ 724 monitor with work surface ground monitoring wire attachments and grounding - see fig. 12 for complete drawing of the model 724 monitor wire connections. Tools required - small blade, screwdriver and wire cutter. Note: two snap fasteners or appropriate connectors...
Page 9: Note:
9 g) attach the tinned model 724 ground wire to the ground terminal of the two-wire connector by inserting the tinned end into opening and securing with screwdriver (fig. 5a). Attach the ring terminal end with a screw (not supplied) to an electrical ground (fig. 7b). Continue with step (2h). H) plug...
Page 10: Caution
10 e) determine how you want to ground the model 724 monitor: • if you are grounding through the ac adapter, perform step (3f.) • if you are grounding through the model 724 ground wire, perform step (3g.) f) attach the tinned ground wire of the ac adapter to the ground terminal of the two-wire conne...
Page 11
11 fig. 6 - cutting off table mat ground snap. Fig. 7a - attaching system grounds. Note work surface and unit are grounded at different locations. Fig. 7b - grounding model 724. Fig. 8 - inserting two-wire connector into rear of model 724. Fig. 9 - inserting 732 plug into rear of model 724..
Page 12: Section 4.
12 section 4. Selection of test voltage and resistance limit tools required - small blade, screwdriver. The model 724 monitor allows for the selection of test voltages (9v or 16v) and resistance limits (10 megohms or 35 megohms). The additional ranges have been added to accommodate global esd requir...
Page 13: Section 6.
13 c) plug the ac adapter into a 3-prong grounded outlet (north american system). Outside north america use appropriate ac adapter (see specifications section 11). The 724 monitor is ready for use. Section 6. Wrist strap connection a) attach a 3m dual conductor ground cord to a 3m dual conductor wri...
Page 14: Section 7.
14 section 7. Fault conditions (refer to fig. 3) red wrist strap lamp (h) accompanied by an audible alarm this indicates that a high resistance condition (greater than 10 megohms or 35 megohms) exists for an operator or wrist strap assembly. If two operators are connected to the monitor the high con...
Page 15: Section 8.
15 section 8. 3m ™ model 3057 standby jack since the activating switches are located in the models 732/733 dual conductor remote input jack, the normal operating procedure is for the operators to disconnect their cords from the remotes when leaving the work station. However, an optional standby jack...
Page 16: Section 11.
16 c) position and mount both remote input jacks in convenient locations. Fig. 16 - inserting model 733 plug into rear of model 724 section 11. Verification procedure for the model 724 monitor the model 724 monitor cannot be recalibrated after the initial factory calibration. However, the following ...
Page 17: Note:
17 • one two-conductor cable with standard 3.5 mm (miniature) phone plug attached on one end and appropriate connectors on the other end to connect to rsb. Note: two-conductor cable must have an isolation resistance of >1 gigohm between conductors. Two separated wires may also be used to obtain high...
Page 18
18 8.5 megohms – high red wrist strap lamp (h) off, green (ok) lamp (1) on, and audible alarm off. 11.5 megohms – high red wrist strap lamp (h) on, audible alarm on (continuous tone), and green (ok) lamp (1) off. I) repeat step (6h) for input #2 of the 732 dual conductor remote input jack. Audible a...
Page 19: Section 12.
19 n) test as in step (6l) above. However, set the resistance as follows and observe the 724 monitor output: 1.3 megohms - yellow low lamp (l) flashing, green (ok) lamp (1) on, and audible alarm off. 1.7 megohms - yellow low lamp (l) off, green (ok) lamp (1) on, and audible alarm off. 29.8 megohms -...
Page 20: Section 14.
20 section 14. Section 15. Additional wrist strap monitoring information suggested reading on wrist strap requirements and wrist strap monitoring: • eia 625 - requirements for handling electrostatic-discharge- sensitive (esds) devices. • en100015/1 - protection of electrostatic sensitive devices. • ...
Page 21: Section 16.
21 section 16. Warranty limited warranty - 3m expressly warrants that for a period of one year from the date of purchase, 3m static control products will be free of defects in materials (parts) and workmanship (labor). Defects occuring during the warranty period will be repaired or products will be ...