APOLLO 491-4597 Digital Grademeter Sensor Screed Grade Control for AP655F Asphalt Paver Spare Parts

APOLLO 491-4597 Digital Grademeter Sensor for AP655F Asphalt Paver

A paving mat is only as level as the grade signal that controls the screed. The APOLLO 491-4597 digital grademeter sensor is the feedback element in that loop on the AP655F asphalt paver: it reads the reference elevation and reports deviations to the machine control system, which then raises or lowers the screed to hold the required grade.

The reference can be a tensioned string line along the run, the edge of an adjacent mat, or an averaging beam carried by the paver. Whatever the setup, the sensor converts the small changes it detects into a clean digital signal, so the control system receives usable data instead of electrical noise from the engine, hydraulic pumps and generator.

Key Features

• Digital signal output: digital processing is far less sensitive to electrical interference than analogue sensing, reducing false corrections that show up as ripples in the mat.
• Finer grade resolution: the sensor resolves small height changes, which supports a tighter tolerance on longitudinal evenness.
• AP655F integration: the electrical interface and mounting match the paver's control architecture, so the machine computer reads the data without adapters.
• Field serviceable: plug-in connector layout lets a fitter replace a failed sensor during a maintenance window rather than stripping the harness.
• Genuine APOLLO part: built to original specification for repeatable performance in dust, vibration and heat.

Product Specifications

When to Replace the Sensor

Grade problems rarely announce themselves as an electrical fault. In practice a failing sensor shows up as a mat that drifts high or low over a long run, a screed that keeps correcting in one direction, or a control panel that logs grade errors while the hydraulics test normal. In those cases the sensor is usually the first item to check, because it sits at the front of the control chain and a biased signal forces every downstream correction.

• Mat thickness varies over a run despite a constant reference.
• Frequent grade alarms that clear after a restart.
• Visible damage or corrosion at the sensor connector.
• Known impact on the sensor arm during transport or site movement.

Ordering Information

Please confirm the machine model AP655F and the part number 491-4597 when sending an inquiry. Single sets and mixed spare parts orders are both accepted. Photos of the original sensor are welcome and will be checked against stock before shipment. Contact our sales team for current pricing and lead time.