This specification is for the purchase of five (5) new nuclear moisture density gauges and the disposal of three (3) existing gauges. The electronic system must meet the following requirements: 7.1.1. Components must be modular and field replaceable. 7.1.2. No warm-up period must be required, except for gas-filled detectors. If warm-up is needed, it must not exceed 15 minutes and must be stated in the user manual. 7.1.3. The gauge must utilize a stable gamma-ray detector for density and a stable thermal neutron detector for moisture. Both detectors must be shielded and correctly positioned. 7.2. The electrical system must operate using one of the following battery configurations: 7.2.1. Rechargeable Battery Pack: • Must provide a minimum of 320 operational hours, based on 8 hours of daily use with 16 hours of downtime before recharge. • Must include chargers compatible with 110/120 VAC and 12V DC vehicle power outlets. • Chargers must fully recharge the battery within 16 hours. 7.2.2. Replaceable Dry-Cell Battery Pack: • Must provide a minimum of 800 operational hours using fresh alkaline batteries under normal usage cycles. • Must support the use of either D-size or AA-size alkaline batteries.
