You're correct, it's not usually mandatory to install a local safety switch next to every electric motor, especially in a large installation like the one you describe. However, it's a very good practice and may be required in specific circumstances. Let's break down the factors

Why it's not always required:
Cost

Installing 1000 local switches adds significant cost.

Space

Space can be a constraint, especially in older facilities.

Design Philosophy

Some installations rely heavily on centralized control and lockout/tagout procedures at the control panel.

Why it often should be considered, and when it might be required



Safety



Maintenance

The primary reason is safety during maintenance, repairs, or adjustments. A local switch allows a technician to physically isolate the motor right at the motor, providing a much safer environment than relying solely on a remotely operated breaker.

Lockout/Tagout (LOTO)

Local switches are critical for effective LOTO procedures. They provide a readily accessible isolation point for maintenance personnel. Without a local switch, LOTO becomes more complex and potentially less reliable.

Emergency Stop

If the motor is involved in a process that could create a hazard, a local emergency stop switch (connected to the motor's control circuit or even directly interrupting power in critical situations) can be crucial.

Practicality



Troubleshooting

A local switch simplifies troubleshooting. You can quickly isolate the motor to determine if the problem lies with the motor itself or the control circuit.

Accessibility

If the motor is far from the main control panel, a local switch saves time and effort during maintenance.

Specific Circumstances (where it may be required by code or best practice)



Conveyors

As you mentioned, conveyors are a prime example. Because of the potential for serious injury from moving parts, local disconnects are almost always required (and very strongly recommended even if not explicitly mandated).

High-Power Motors

Larger motors (e.g., above a certain horsepower or kilowatt rating) often have a higher risk associated with them and are more likely to have local disconnects. (This is more of a guideline than a hard rule.)

Hazardous Locations

Motors in hazardous locations (classified areas with flammable gases, vapors, dust, etc.) often require special switches suitable for the environment (explosion-proof, intrinsically safe, etc.). Codes for hazardous locations almost always mandate a means of local isolation.

Remote or Difficult Access

If the motor is located in a hard-to-reach area, a local switch simplifies isolation.

Specific Industry Standards

Some industries (e.g., mining, oil and gas) have stricter standards for motor isolation.

Company Safety Policy

Many companies have internal safety policies that exceed minimum code requirements and mandate local disconnects for certain types of equipment.

Risk Assessment

A thorough risk assessment of the application is critical. If the assessment identifies a significant risk associated with working on the motor, a local disconnect is a logical mitigation measure.

IEC Standards and Obligations

While I cannot definitively state that a specific IEC standard obligates a local disconnect switch for every motor in every situation, here's what to consider:

IEC 60204-1 (Safety of machinery - Electrical equipment of machines)

This standard addresses the electrical safety of machinery. While it doesn't explicitly mandate a switch at every motor, it emphasizes the need for a readily accessible and reliable means of isolation. The interpretation of "readily accessible" often leads to the installation of a local disconnect. It also describes that a main switch or main isolator is required which can cut off all electrical power for a system.

IEC 60364 (Low-voltage electrical installations)

This is a broad standard for electrical installations. It covers many aspects of motor circuits, but it's unlikely to mandate a local disconnect for every motor. However, it does require adequate protection and isolation, and a local switch can be the best way to achieve that.

IEC 61439 (Low-voltage switchgear and controlgear assemblies)

This relates to the construction and testing of switchboards. It is very unlikely to specify a switch per motor.

Considerations for Functional Safety (IEC 61508, IEC 61511)

If the motor is part of a safety-related system (SIL-rated), then a local disconnect might be required to ensure the system can be brought to a safe state in an emergency.

National Deviations

Remember that national implementations of IEC standards can have variations. A particular country might have a specific regulation requiring local disconnects in certain situations.

In summary



No general IEC obligation for a local switch for every motor. Strongly recommended for safety and LOTO compliance. Required in specific situations (conveyors, hazardous locations, high-power motors, difficult access, industry-specific requirements, based on risk assessment). Consult local electrical codes and regulations. Consider company safety policy.Recommendations

1.

Conduct a thorough risk assessment for your installation. Evaluate the hazards associated with each motor and the need for local isolation.2. Review relevant IEC standards, local electrical codes, and company safety policies.3. Consider the practical benefits of local switches for maintenance, troubleshooting, and LOTO.4. Document your decision-making process. If you decide not to install local switches, document the reasons why, and describe the alternative safety measures that will be in place.Instead of thinking about it as an "obligation," frame it as a "best practice" and a critical safety measure. In many cases, the cost of not having a local switch (in terms of potential accidents and downtime) far outweighs the cost of installation. Flag for review