Approved Burner Management Systems for smaller packaged boilers have what characteristic?

Burner Management Systems (BMS) for smaller packaged boilers are designed with specific characteristics that balance safety, usability, and operational efficiency. The correct answer indicates that these systems have a limited selection of field-configurable parameters. This limitation is intentional, as it helps ensure that the systems remain simple and safe for operation without compromising the integrity of the boiler's function.

Smaller packaged boilers typically have less complex operations compared to larger systems, which means that while some parameters may be adjustable by operators in the field, they are restricted to a few predefined options to maintain safety standards and operational reliability. Limiting configurability reduces the risk of operator error and ensures that safety protocols are consistently adhered to.

In contrast, fully-configurable systems, while beneficial in some contexts, are more suited for complex installations requiring in-depth customization and control. Allowing complete configurability in smaller systems could lead to unsafe operations if not managed properly. Therefore, the design of these systems focuses on providing essential controls that are safe for operators to adjust while minimizing the risk of misconfiguration.