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U.S. Department of Labor


Mine Safety and Health Administration
1100 Wilson Boulevard
Arlington, Virginia 22209-3939
ISSUE DATE: February 25, 2011

PROGRAM INFORMATION BULLETIN NO. P11-01

FROM:              LINDA F. ZEILER LINDA F. ZEILER
                       Acting Director of Technical Support

                       KEVIN G. STRICKLIN  
                       Administrator for
                       Coal Mine Safety and Health

SUBJECT:     Redesign of the Emergency Stop Circuits on Model BHAC Joy Mining
                    Machinery (formerly Stamler Corporation) Battery Coal Haulers

Scope
This Program Information Bulletin (PIB) applies to mine operators, miners' representatives, Mine Safety and Health Administration (MSHA) enforcement personnel and other interested parties.

Purpose
The purpose of this PIB is to inform the mining community that MSHA has approved a safety upgrade to the emergency stop switch circuit on the Joy Battery Coal Hauler (Approval No. 18-A060011-0). Additionally, this PIB includes recommendations concerning operation of the emergency stop switch.

Information
Joy Mining Machinery has designed and received MSHA approval for a safety upgrade to the emergency stop switch circuit on the Joy Battery Coal Hauler (Approval No. 18-A060011-0). The upgrade ensures against inadvertent movement of the machine when the emergency stop switch is activated by providing a second shutdown circuit that prevents the pump from restarting on release of the emergency stop switch.

MSHA recommends that mine operators:

The second emergency stop circuit is designed and wired through the Programmable Logic Controller to ensure that the machine tram circuit is shut down and remains shut down when the emergency stop switch is activated. If the emergency stop switch is activated and any machine or display lights remain on, this indicates that the machine circuits remain energized and a problem exists. One of these problems could be failure of the circuit breaker to trip on activation of the emergency stop switch. Joy Mining has released a Service Bulletin (attached) that was distributed to all of its customers of equipment utilizing MSHA Approval No. 18-A060011-0. The Service Bulletin provides information about an upgrade kit and describes the wiring change to install the upgrade of the emergency stop switch circuit.

Background
MSHA became aware of an incident where activation of the emergency stop switch on a Joy Hauler caused the machine to come to a stop, but did not deenergize the machine. It was noted that the lights were still on and when the emergency stop switch was released, the pump motor restarted, which released the brakes and enabled the machine to be trammed. This could have caused unintentional movement of the machine.

MSHA's authority for this PIB
The Federal Mine Safety and Health Act of 1977, as amended, 30 U.S.C. § 801 et seq.; 30 CFR §§ 75.523

Internet Availability
This information bulletin may be viewed on the Internet by accessing MSHA's home page at (http://www.MSHA.gov) and then choosing Compliance Info and Program Information Bulletins.

MSHA contact persons for this bulletin
Technical Support, Approval and Certification Center
Kenneth Porter, (304) 547-2030
E-mail: porter.kenneth@dol.gov

Coal Mine Safety and Health, Safety Division
John Arrington, (202) 693-9549
E-mail: Arrington.john@dol.gov

Distribution
Program Policy Manual Holders
Underground Mine Operators

   - Attachment