BWTS calibration after controller replacement: reconnect certificates to real signals
Updated
Sea Clean can verify BWTS instrument signals after a PLC or input-module replacement and calibrate instruments where required. Keep valid sensor evidence while checking the new controller's scaling and channel assignments.
Key takeaways
- Changed controller modules
- Instrument certificates and channel map
- Before/after configuration
- Required signal and alarm tests
Get it done with Sea Clean
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Send an order request against our quotation
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Separate sensor condition from controller change
Collect the existing certificates, instrument register and before/after controller configuration. A new input module does not automatically make every sensor inaccurate, but it can change how signals are interpreted. Identify the channels touched by the work and the functions that depend on them.
Check mapping, range and fault behaviour
Verify channel identity, units, scaling, normal indication and the handling of out-of-range or failed signals against the installed design. Record local and controller readings at agreed points. Test changes through a controlled procedure so simulated values are not mistaken for live process measurements.
Issue a clear combined record
The handover should distinguish existing sensor calibration evidence, new calibration work and controller-loop verification. Sea Clean can quote these separately or combine them into one attendance. This preserves useful records while giving the manager evidence that the changed control system reads the actual instruments correctly.
Illustrative procurement scenario
A replacement input module restores communication but displays the wrong pressure range. The order targets scaling and channel verification, with sensor calibration included only where due or technically required.
Get it done with Sea Clean
Sea Clean carries out annual instrument calibration across EC BWTS manufacturers and variants, with calibration certificates and clearly defined checks. Send the instrument register, due dates and vessel schedule to arrange the work.
Sea Clean services around 400 vessels and supplies around 2,000 kits per year. Get BWTS service, annual calibration, spare parts and water-testing coordination organised through one technical contact.
Email the checklist below with your vessel, equipment and required date. We will quote the defined work or supply. To proceed, reply with the quotation reference and purchase-order details so scope, price and arrangements can be confirmed.
Service and attendance: Arrange BWTS service, calibration and testing
Frequently asked questions
Must every sensor be recalibrated after a PLC change?
The scope depends on the change, existing evidence and applicable requirements. Sea Clean can distinguish instrument calibration from the controller verification needed after replacement.
Sources
- US EPA — VGP and VIDA interim requirements — US applicability, transition guidance and links to monitoring and sample-handling references.
- US EPA — 2013 VGP — Read with current interim guidance and the vessel's applicable requirements.
- ERMA FIRST — FIT system overview — FIT process and component arrangement; check the vessel's installed configuration.
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