This manual is meant to be used by qualified personel only. Make sure to have read the safety precautions at the beginning of this manual and the warnings/cautions contained in the referred chapter prior to carrying out any servicing. This manual contains the following chapters: GENERAL INFORMATION Describes the introduction and safety considerations. PERFORMANCE TEST Describes the performance tests for checking performance of the instrument. ADJUSTMENTS (for DL1540C DL1540CL Describes the adjustments which can be adjusted by users. PRINCIPLE OF OPERATION (for DL1540C DL1540CL Describes the function block diagrams and principle of operation. TROUBLESHOOTING (for DL1540C DL1540CL Describes procedures for troubleshooting and how to handle in case parts need to be replaced. SCHEMATIC DIAGRAM (for DL1540C DL1540CL Describes the system configuration diagram. CUSTOMER MAINTENANCE PARTS LIST Contains exploded views and a list of replaceable parts. Specifications are not included in this manual; for specifications, refer to IM 701530- 01E.