© 2007 ideal industries 1 of 38 meter safety in the workplace ideal’s test and measurement meter...

Meter Safety In the Workplace© 2007 Ideal Industries www.idealindustries.com 1 of 38

IDEAL’s Test and MeasurementMeter Safety in the Workplace

Sponsored by Bud Grant, ASM IDEAL Industries, Inc


Agenda

• Awareness of potential Measurement Hazards– OSHA and NFPA Explained– Arc Flash/Arc Blast– Who’s responsible for safety– Tools to keep you safe


Meters and Safety in the workplace

OSHA (YOU Shall DO)1926.416 29 CFR Ch. XVII (7-1-94 Edition)

(g) Use of Equipment. (1) Work on energized equipment. Only qualified persons may work on electrical circuit parts or equipment that have not been de-energized. Such persons shall be capable of working safely on energized circuits and shall be familiar with the proper use of special precautionary techniques, personal protective equipment, insulating and shielding materials, and insulated tools.

NFPA 70E (How To)130.2(C) Approach to Live Parts Operating at 50 volts or More:

No qualified person shall approach or take any conductive object closer to exposed live parts operating at 50 volts or more than the Restricted Approach Boundary [minimum 3’ 6” for exposed fixed circuit part]……unless… The qualified person is insulated or guarded from the live parts operating at 50 volts or more 70E 130.2(C)(1)


Meters and Safety in the workplace

– Persons shall be trained in safety related work practices and procedures

– A person should be able to identify and understand the relationship between the electrical hazards and possible energy.

• 110 Qualified Personal• 110 6.(D)(1)( C) Proper Skills and Cognitive abilities to

know the hazards and use proper Personal Protective Equipment.

Article 110: (A) Training Shall apply to employees who face risk of electrical hazard


Why should we be Concerned?

• An electrician troubleshooting a live 480V motor control center receives serious second- and third-degree burns from an electric arc. The cause? – Meter was incorrectly

switched on his multimeter to read resistance instead of voltage.


Why should we be Concerned?

• Two electricians are severely burned — one fatally — while testing for voltage in a motor starter. One held the multimeter while the other applied the meter's probes to energized terminals. One electrician's movement caused one test lead banana plug (energized from the circuit under test) to pull loose from the multimeter jack. – The plug made contact with

the starter's grounded metal enclosure and initiated a high-energy arc.


Who is Responsible

• Personal Protection Equipment (PPE)– Arc Flash, insulating

and shielding materials

– Insulated tools – Test Equipment

110 6.(D) (1) (a) Persons shall be familiar with the proper use of special precautionary techniques


Who is responsible

• (E) Electrical safety program shall identify the procedure for working on, or near live parts >50 Volts

• (F) A procedure for evaluating hazard and risk associated with work on or near live parts operating above 50 volts, where an electrical hazard exists, before work can be started.

• The decision to work on energized circuits should be in accordance with guidelines as specified in Article 130.1 (A)

110.7 An employer shall implement an overall electrical safety program that directs the activities of employees when exposed to electrical hazards or risk.


Ratings for Test Equipment

– IEC or UL 61010 Category ratings – Test equipment must be selected based on

the intended use and expected voltage or current ratings.

– Cost should not be a part of the equation.

110.9 (1)Test instrumentation, equipment and associated accessories must be rated for the circuits and equipment to which they will be connected.



• International Electro-technical Commission or IEC– IEC 61010 requires an instrument provide

protection against “over-voltage impulse transients” - voltage spikes.

– Electric Shock or burns – Mechanical hazards



• International Electro-technical Commission or IEC– IEC 61010 and is the basis for:

• ANSI/ISA-S82.01-94 (US)

• CAN C22.2 No. 1010.1-92 (CAN)

• EN61010-1:1993 (EUR)

• UL-61010B-1

• 61010B-1 incorporates features of the IEC 601010 standard,

but this standard has improved safety benefits over the old UL384 and UL1244 standard



• High Voltage transients come from lightning, large inductive loads being switched on and off, or capacitive discharge – If a lighting strike was to hit

your electrical service a certain amount of energy or impulse would travel and be dissipated by the electrical service.

– The closer to the source of the impulse the Higher available fault current.


Impulse Fault– The closer to the source of the impulse the Higher

available fault current. – If an instrument was to be hit by an impulse and a

fault condition was to occur the Available energy “Fuels” the Fault.

– Lets use the example of water or water pressure.– The larger the pipe the Greater the potential– The closer to the supply the Greater the potential

Fireman with a 4 inch

hose

Faucet with ½ inch

supply line



• Rating on input protection on Test instruments and Equipment are in order of potential available energy. The closer you are to the source the Higher the Category rating of the equipment

• IEC 61010 breaks energy rating down to four Categories:

– CAT IV Origin of installation, – CAT III Distribution Level, – CAT II Local level, – CAT I Signal Level,



CAT III-600V or CAT II-1000V?The greater the source impedance,

the lower the Category:• CAT III-600V:

– 6 kV impulse – 2 Ohm test source

• CAT II-1000V:– 6 kV impulse – 12 Ohm test sourceA CAT III-600V 6kV test

impulse has 6 times the current of a CAT II-1000V 6kV test impulse!

• Voltage rating by itself can be misleading.– CAT III-1000V (8kV

transient) is safer than CAT III-600V (6kV transient)

– But CAT III-600V is safer than CAT II-1000V

What “Voltage” In the Rating Really means Remember Ohm’s Law Earlier


Certified Devices and Equipment

• Pay close attention to the safety rating on the equipment. – Never use equipment that is not

properly rated [110.9 (1)]• Look for tools that are

Certificated by an independent lab, – UL , IEC, CSA.

• Never use accessories that are not recommended or rated for your tester or environment.

IEC Cat ratings

The New UL 61010B-1 standard incorporates

features of the IEC 601010 standard. This standard has

improved safety benefits over the old UL 1244 standard


Example, Visual Inspection

– If an instrument or equipment show any signs of damage it most be removed from service.

– Equipment may not be returned to service until it is properly repaired or replaced.

110.9 (3) Visually Inspect Equipment and all associated accessories for defects and damage


Example, Visual Inspection

– Check for any contaminate on the test leads, tester case, holsters, and accessories.

– Never use testers that have signs of cracked case, contaminants, loose or defective components.

– Most defects are the result of normal wear around input connectors or terminals, function switches and controls.

– Operational defects may not be so easily detected through a visual inspections.

• Low Batteries, Defective leads, fuses and etc.

110.9 (3) (cont)Visually Inspect Equipment and all associated accessories for defect and damage.


Example, Visually Inspection

• An easy test for testing leads is to use the meter’s ohms function.

• Short the leads and move the wire around the input connectors and lead grips.

– If the meter reads < 0.3 ohms leads should be OK, if > 0.5 ohms leads may need to be replace.

• Some users are now using Fused lead. You may only need to change a fuse.

• Check for the following.– Insulation not damaged: melted or

discolored, cut, cracked, or stretched– Connectors: no insulation pulled away

from end connectors– Probe tips: arc burns, loose or broken

Visually inspect Test Leads


Common Mistakes Made

• Make sure not to exceed the Max input of your meter.

– Most common mistake is to measure voltage with the leads in the current inputs.

– Current inputs are very low resistance. It appears as a short circuit to Voltage.

– For current input protection most DMMs’ are Fused.

– Look for high energy fusing.

Current

Protection

Fuse

Current input on a Digital multimeter normally has very low resistance And appears as a short circuit if voltage is measured

Ideal 61-490 series give a probe error message and High audible warning if

this mistake to done.



• Example: AC or DC voltage measurement with function switch in Ohms.

• Most Ideal meters are Overload Protected and the protected levels are listed in the operation manual. – User my get a false sense that the

circuit is de-energized when in fact the circuit my be energized.

Ideal 61-700 series will give you a Hi-V and audible warning if you make

this Mistake

Function Switch in wrong function for attempted measurement



• Example: 2,300 voltage measurement with an instrument rated for Low Voltage (600V AC/DC.)

• Overload Protected can not protect you from this Kind of mistake.

• Most Overload protected is rated based on instruments highest voltage measurement rating.

There are Bold Electricians and Old electricians, but not many Bold-Old

ones

•Using a meter in an area above its stated rating


Common Safety Hazards

• Select meter with the proper UL/IEC Category rating for the environment that user is going to be working in.

High Voltage transients from lightning, large inductive loads being switched on and off, or capacitive discharge.


When should work begin

– All possible sources are Identified– Isolate loads, open disconnect devices for each load– If possible, visually verify disconnect devices– Apply lockout/Tag-out devices in accordance to documented

procedures or practices– Use properly rated Voltage Detection device to test Phase

conductor or parts. • Measure both phase to phase, and phase to ground.• Use the three point measurement method

• Measure a know source first, the unknown, then back to the known

120.1 An electrical safe condition does not exist until the following conditions are met.


When should work begin

– When there is a possibility of inducted or stored energy present ground the phase conductors

• When it could be possible that a de-energized circuit come in contact with a energized circuit use grounding connection devices rated for the possible available fault.

• Refer to 120.1 for an approved grounding connector..

– Induced (Ghost) Voltage conditions are cause by inductive ( or Capacitive) voltage into conductors in close proximity to other conductors.

120.1(cont.) An electrical safe condition does not exist until the following conditions are met.


Induced or Ghost Voltage

• Induced Voltage conditions can be tricky to detect.

• The input impedance of most Digital Multimeters are in the range of 10 Meg-Ohm

• This impedance is not sufficient to dissipate induced or what is sometimes call Ghost voltage.

• Low impedance testers or solenoid testers are very useful when testing were induced energy may be a problem.


Lockout/Tagout

• This is to ensure that when hazardous energy is removed that there is a controlled process that insures this state.

• That there is a method to verifie the absence of voltage using and approved voltage testing device.

• The employer shall provide training as required to ensure employees understand all aspects of the Lockout/Tag-out procedures. – 120.2(E)(2) Employer must provide the

necessary equipment to implement the requirements of lockout/tag out procedure.

120.2 Establishes the requirement for the implementation for Lockout/Tag-out procedures


Lockout/Tag-out

– Many world class companies already have LO/TO programs in place

– IDEAL conducts review Lock-out/Tag out seminars at distributors and at end user sites.

– Training instruction material is also available if the end user wants adapt to current safety programs already in existence.

120.2(F) The employer must implement lockout/tag-out procedures for the company in accordance with and including elements and requirements as defined in article 120.


Testing

– The testing device • Who will use the testing device

– The boundary of the safe zone established by the Lockout/tag-out

– Requirements for testing a conductor before it is touched

– Retesting if conditions change or job location has been left unattended.

120.2(F)(2)(f) Testing procedures shall establish the following.

Meter Safety In the Workplace© 2007 Ideal Industries www.idealindustries.com 30 of 38*OSHA 1910.333 (a)(1) & NFPA 70 E 2-1.1.1

Qualified electrical workers shall not be asked to work on equipment that is “hot” or “live” except for two reasons :

1. De-energizing introduces additional or increased hazardsa) Cutting ventilation to a hazardous locationb) Interruption of life support equipmentc) Deactivation of emergency alarms

2. It is infeasible due to equipment design or operational limitationsa) Doing voltage testing for diagnostics or troubleshooting that

can only be performed with the circuit energized

When Can You Work Hot?

NFPA-70E 130.1 Justification for Work


Approach Boundaries to Live parts

– defined to four different approach boundaries.

• Limited Boundary

• Restricted Boundary

• Prohibited Boundary

• Flash protection Boundary

– Approach boundaries are defended in Table 130.2 ( C)

130.2(A) Shock hazards analysis shall determine level personnel are exposed to hazards, and assess boundary Limits and requirements for PPE.


Approach Boundaries to Live parts

• Only Qualified Person shall perform testing work on or near live parts operating at >50 volts [110 6.(D) (1) (c )]

• Each person should be training to understand how to use specified test instruments and equipment

•130.4 Test instrument and equipment use.


Not just Your Test Meters !!

– Employee working in areas where there are electrical hazards shall be provided with, and shall use, protective equipment that is designed and constructed for the specific part of the body to be protected and for the work to be performed.

130.7 (A) Personal and Other Protective Equipment


OSHA Qualified Workers

(g) Use of Equipment. (1) Work on energized equipment. Only qualified persons may work on electrical circuit parts or equipment that have not been de-energized under the procedures or paragraph (b) of this section. Such persons shall be capable of working safely on energized circuits and shall be familiar with the proper use of special precautionary techniques, personal protective equipment, insulating and shielding materials, and insulated tools. (OSHA Standard)

•§ 1926.416 29 CFR Ch. XVII (7-1-94 Edition)


OSHA Protection Safeguards

(a) Use of protective equipment.(1) Personal protective equipment.(i) Employees working in areas where there are potential electrical hazards shall be provided with, and shall use, electrical protective equipment that is appropriate for the specific parts of the body to be protected and for the work to be performed.

§ 1910.335 Safeguards for personal protection:


Interpreting OSHA

Insulated hand tools (which conform to IEC 900 and ASTM F1505 standards) rated for the voltage involved would be considered insulation of the person from the energized part on which work is being performed. Generally, those tools which have a max. rated voltage of 1,000 volts for AC applications and 1,500 volts for DC applications would be suitable for work covered under the provisions of 29 CFR 1910 Subpart S.

•Official Interpretation From OSHA Officials:


Do you Test or Calibrate you Equipment?

• 250.1 Maintenance requirements for personal safety and protective equipment as listed must be maintained in accordance with the manufacturers recommendations or listing

• 250.2 Inspection and testing of protection equipment and protections tools– Visual inspection for damage or defects before use and intervals as

required, but not to exceed 1 year.

– Shall be verified by appropriate testing, at acceptable interval, to acceptable standards or practices, to insure proper operation.


Thank you

You may want to refer to the Following

• NFPA 70E 2004, Handbook for electrical safety in the workplace.• ANSI C62.41 - IEEE Recommended Practice on Surge Voltages• IEC 60101• UL 601010B• Case histories come from an IEEE paper entitled “Personnel Safety and

Plant Reliability Considerations in the Selection and Use of Voltage Test Instruments,” (IEEE Transactions on Industry Applications, Vol. 33, No. 2, March/April 1997),written by H. Landis Floyd II and Brian J. Nenninger.

IDEAL Industries, IncTest and Measurement Division

1 Becker PlaceSycamore, Il 60178

(800) 435-0705

© 2007 ideal industries 1 of 38 meter safety in the workplace ideal’s test and measurement meter...

Documents