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Department of Transportation - Division of Maintenance <br />Structure Maintenance & Investigations <br />INSPECTION COMMENTARY <br />SCOPE AND ACCESS <br />***Bridge was under construction at the time of inspection. No functional testing could be performed.*** All mechanical & electrical <br />defects still present. <br />Bishop Canal Bridge, 29C0114, is a Swing Span Movable Bridge located on Eight Mile Road west of Interstate 5. (38.058417, - <br />121.418419) <br />This report documents the inspection of mechanical and electrical items required for normal operation of this movable bridge. Inspection <br />includes visual and electrical testing of as -installed machinery components and verification of control sequencing and operation. <br />Inspections are not intended to perform second -level investigations such as dismantling bearings or NDT analysis. Work <br />Recommendations provide for normal maintenance and operation of as -installed equipment and not for upgrading existing equipment. <br />County Maintenance Staff stated only one call for an opening in seven years. Maintenance crew reported that they open periodically (6 <br />per year) to exercise machinery. <br />EQUIPMENT INFORMATION <br />Electrical Service info: Unknown Amps, 120/240V, 3-phase, 4W <br />PG&E #:1011500097 <br />Location: North-East entrance of bridge <br />End Jack Machinery: <br />West --5 hp, 240V, 3-phase motor driven worm gear screw jacks with hydraulic actuator to pull the keyed jack blocks (total 2) (FLA = <br />15.2A *NEC) <br />East -- 10 hp, 240V, 3-phase motor driven worm gear screw jacks with hydraulic actuator to pull the keyed jack blocks (total 2) (FLA = <br />28A *NEC) <br />End Lock Machinery: <br />East and West - Two 2 HP, 120-volt, single phase motors at each end for pulling and driving the end locks (total 4). (FLA = 6.8A *NEC) <br />Center Machinery: <br />Hydraulic pump motor: 240V, 5hp, 3-phase <br />Twin hydraulic double acting slewing cylinders. Directional valves with flow control operate the cylinders. (FLA = 15.2A *NEC) <br />Sump Pump 240 V Single 1-phase, with built in float switch (see work recommendation) <br />Motors feeder main voltage measured before operation : 247 V <br />The bridge remained closed due to a recent electrical issue, which the local maintenance crew is addressing through Federal Aid Project <br />No. BRLS-5929(229). The crew determined that opening the bridge during the inspection could prevent it from closing properly, as they <br />lacked the means to close it if needed. Consequently, the bridge crew decided not to open the bridge during the inspection. Only the <br />hydraulic motor, which does not require opening the bridge, was operated during the inspection. <br />Insulation resistance readings measured before operation, and current readings measured <br />during operation are as below: <br />(All measurements are from the 2023 inspection no new measurement were taken) <br />East End Jacks <br />#1 4.5 M-Ohm 14.3 Amps -Lifting 14.4 Amps -Lowering <br />#2 30 M-Ohm 13.2 Amps -Lifting 12.6 Amps -Lowering <br />West End Jacks <br />#1 30 M-Ohm 7.6 Amps -Lifting 7.1 Amps -Lowering <br />#2 200+ M-Ohm 7.1 Amps -Lifting 6.8 Amps -Lowering <br />Hydraulic Pump 15 M-Ohm <br />15.8 Amps peak current for 2 seconds <br />8.5 Amps Opening <br />7.8 Amps Closing <br />East End Lock (motor 1 &2) <br />Pulled 4.4 Amps <br />Drivin 4.0 Amps <br />West End Lock (motor 1&2) <br />Pulled 4.2 Amps <br />Drivin 4.1 Amps <br />Printed on: Monday 06/23/2025 03:37 PM Page 4 of 9 29C0114/AAAZ/153158 <br />