Onshore & Offshore

Grounding and bonding checks- confirm the integrity of the ground system and bonding system by measuring the resistance of bonds to ensure bonding to all metallic surfaces is in place.

Cold loop checks and megger checks- confirm that all cable and conductors are terminated to the correct terminal blocks, as well megger checks apply a voltage across the cable conductor and insulation to confirm that the cable has not been damaged or punctured to degrade the dielectric properties of the cable.

Hot loop checks- confirm calibration settings and ranges of each control loop from the HMI to the end device including all cables and instruments. This confirms that ranges and setpoints are correct for each control point.

AC phase checks- verify the installation of each electrical phase in the proper order using a phase rotation meter.

Transformer checks- prior to the first energization of the transformer, oil samples are taken as well as samples taken after energization. The samples are compared to see if any differences could indicate an internal problem within the transformer. Winding resistance measurements are taken as well to measure insulation resistance. Transformer ratios are measured once tap changes are set to confirm that the primary and secondary windings are correct.

Open circuit tests– conducted to measure the no-load current losses as well as short-circuit tests performed with reduced voltage to the primary winding to measure full-load current losses.

During protection relay testing, primary and secondary injections are performed on CTs and PTs to verify relay inputs are correct.

During interlock verification, interlocks are verified by operating equipment without bus voltage applied, and the different operating configurations are verified to confirm that interlocks are functioning correctly before applying any bus power to the system.

AC and DC hi-pot tests measure the ability of a dielectric to withstand rated and transient voltage.

Battery discharge tests– confirm how many hours of rated voltage and current can be supplied during charge and discharge cycles.

Pre-commissioning is complete once you’ve completed all your checklists and verified that each piece of equipment meets the technical requirements of the project. Pre-commissioning activities test equipment as standalone items. Tests during pre-commissioning don’t necessarily operate the equipment as a system yet. Each piece of equipment is individually confirmed to be ready for further commissioning tests.

Pre-commissioning is also known as vendor startup since each vendor’s equipment is started for the first time on-site to confirm the function of each piece of equipment. Following pre-commissioning, we can now move into com Sometimes pre-commissioning includes installation of filters, packing of distillation columns, molecular sieve beds, refractory dry out, instrument/ electrical and motor loop testing, etc. All the findings/deviations must be noted in the punch list.