System Overtime Management
A high-performance on-premise Overtime Management System that automates complex manufacturing shift calculations, real-time validation workflows, and multi-department Excel reports with embedded digital signatures, eliminating manual errors and cutting reporting overhead by 90%.
1. Context & Problem Statement
Managing overtime across hundreds of manufacturing operators in multiple departments (Assembling, SMD, PCBA, etc.) involved complex variables, including 3-shift rotations, mixed employment statuses (Contract, Magang, Outsourcing, Permanent), and differing workweek policies (5-day vs. 6-day). The previous manual, spreadsheet-based workflow was prone to human error in calculating hours and break times, lacked real-time visibility, and required hours of administrative overhead each day to compile reports and collect physical signatures.
2. System Architecture & Workflow
[ 1. SUBMISSION ]
Leader/Admin selects Dept, Line, Shift, Date, Hours & Operators
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Schedule Engine automatically computes Start/End Times & Break Deductions
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Stored into MS SQL Server Database (Status: PENDING)
[ 2. REAL-TIME VALIDATION & APPROVAL ]
Operator verifies attendance (Scan NIK / Digital TTD) ──> Status: Operator Approved
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Live UI updates via 3-second AJAX Polling (No page refresh needed)
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Admin reviews, adjusts real duration & approves ───────> Status: Admin Approved
[ 3. REPORTING & EXPORT ]
Admin clicks "Daily Report" (Single or Multi-Department Filter)
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`PhpSpreadsheet` builds formatted Excel Workbook:
├── Sheet 1: `SUMMARY` (Line/Shift & Status breakdown separated per Dept)
└── Sheet 2-N: Category Sheets
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Embeds Digital Signature PNGs from File Server directly into table rows
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Instant `.xlsx` File Download (< 5 seconds)
3. Technical Highlights & Automation
Developed a responsive, on-premise MVC web platform built with PHP, SQL Server, Tailwind CSS, and Vanilla JavaScript, optimized for air-gapped intranet environments. Key automations include a Rule-Based Schedule Engine that instantly computes start/end times and mandatory break deductions based on work patterns; a Dual-Tier Approval Workflow powered by 3-second background AJAX polling for real-time status updates; an Automated Multi-Department Excel Generator (PhpSpreadsheet) that dynamically splits summaries and embeds digital signature images (PNG) per department; and an Integrated Gemini AI Assistant for automated workforce overtime analytics.
4. Measurable Results & Impact
- 90% Reduction in Administrative Overhead: Cut daily overtime reporting and SPKL compilation time from 1–2 hours per day down to under 5 seconds with one-click automated Excel exports.
- 100% Calculation Accuracy: Eliminated manual entry discrepancies in overtime durations, shift differentials, and break deductions, ensuring payroll compliance and error-free audit trails.
- Real-Time Operational Visibility: Enabled plant leaders and management to track overtime trends, departmental rankings, and monthly workload allocations instantly through interactive dashboards.
- Paperless & Accelerated Validation: Streamlined on-the-floor operator verification and approval flows, significantly minimizing paper waste and approval bottlenecks.
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