Yes, the neutral bar should be bonded to the can and ground bar.

In the absence of a grounding conductor between the main service and the sub-panel, bonding the neutral bar to the can and ground bar is essential for electrical safety. Direct Path to Utility Earth Ground

By bonding the neutral bar to the can and ground bar, you ensure a direct path for fault current to flow back to the utility's earth ground. This path is important for tripping breakers and preventing potentially hazardous voltage surges.

Fault Current Clearance

Without a bonding jumper, fault current may have to take alternate paths to reach the utility's earth ground, such as through the grounding electrodes of the sub-panel. However, these paths may have higher resistance, leading to potential breaker nuisance trips or delayed fault clearance.

Electrical Code Compliance

In most electrical codes, including the National Electrical Code (NEC), the neutral bar must be bonded to the ground bar for sub-panels supplied by a detached main service.

Additional Considerations



Check for Voltage Differences

Before bonding the neutral bar, it's important to verify that there are no significant voltage differences between the main service and the sub-panel. This can be done with a voltmeter.*

Use Appropriate Equipment: Ensure that the bonding jumper is properly sized and installed according to code requirements.In summary, bonding the neutral bar to the can and ground bar in the sub-panel is necessary for electrical safety and code compliance when the main service and sub-panel are separated by a significant distance and a grounding conductor is not feasible. Flag for review