30 CFR §75.829
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- (a)Conditions of use. Tramming the continuous mining machine in and out of the mine and from section to section must be done in accordance with movement requirements of high-voltage power centers and portable transformers (§ 75.812) and as follows:
- (1)The power source must not be located in areas where permissible equipment is required;
- (2)The continuous mining machine must not be used for mining or cutting purposes, unless a power center is used in accordance with §§ 75.823 through 75.828 and §§ 75.830 through 75.833;
- (3)Low-, medium-, and high-voltage cables must comply with §§ 75.600-1, 75.907, and 75.826, as applicable; and
- (4)The energized high-voltage cable must be mechanically secured onboard the continuous mining machine. This provision applies only when using the power sources specified in paragraphs (c)(2) and (c)(3) of this section.
- (b)Testing prior to tramming. Prior to tramming the continuous mining machine,
- (1)A qualified person must activate the ground-fault and ground-wire monitor test circuits of the power sources specified in paragraph (c) of this section to assure that the corresponding circuit-interrupting device opens the circuit. Corrective actions and recordkeeping resulting from these tests must be in accordance with §§ 75.832(f) and (g).
- (2)Where applicable, a person designated by the mine operator must activate the test circuit for the grounded-phase detection circuit on the continuous mining machine to assure that the detection circuit is functioning properly. Corrective actions resulting from this test must be in accordance with § 75.832(f).
- (c)Power sources. In addition to the power center specified in § 75.825, the following power sources may be used to tram the continuous mining machine.
- (1)Medium-voltage power source. A medium-voltage power source is a source that supplies 995 volts through a trailing cable (See Figure 1 of this section) to the continuous mining machine. The medium-voltage power source must—
- (2)Step-up transformer. A step-up transformer is a transformer that steps up the low or medium voltage to high voltage (See Figure 2 in this section) and must meet the following requirements:
- (i)The trailing cable supplying low or medium voltage to the step-up transformer must meet the applicable requirements of 30 CFR part 75;
- (ii)The high-voltage circuit output of the step-up transformer supplying power to the continuous mining machine must meet the applicable provisions of § 75.824;
- (iii)The step-up transformer enclosure must be—
- (A)Securely mounted to minimize vibration on:
- (B)Grounded as follows:
- (1)Connected to the incoming ground conductor of the low- or medium-voltage trailing cable;
- (2)Bonded by a No. 1/0 A.W.G. or larger external grounding conductor to the continuous mining machine frame; and
- (3)Bonded by a No. 1/0 A.W.G. or larger external grounding conductor to the metallic shell of each cable coupler.
- (C)Equipped with: