- What is the meaning of an "UL File Number"?
- Where can the "UL File Number" be found by maxon documents?
UL stands for "Underwriter Laboratories" and is an US certification authority. An UL certification is required by devices and machines which are imported or in use in the US market.
Although maxon controllers are not UL approved in general the unassembled PCBs of all maxon controllers (e.g. ESCON, EPOS4) are UL approved.
The so-called "UL File Number" of the unassembled PCB is present in the chapter "Standards" of most maxon controller's "Hardware Reference".
The "UL File Number" (e.g. E207844) is not the number of an UL standard. The "UL File Number" is like a registration number provided to a product or a component based on an UL approval. The "UL File Number" of an unassembled PCB listed by maxon's "Hardware Reference" refers to the PCB material and its manufacturer. This means that the manufacturer of the unassembled PCB has successfully performed an UL certification for this kind of PCB material in use by his production for the maxon's controller PCB (and this is also checked at the production site periodically by an UL authority).
UL has a database of all "UL File Numbers". Any "UL File Number" can be retrieved on the base of an UL account which grants access to UL's database.
The data base sheet (formerly called "Yellow card") of a concrete "UL File Number" present by the UL's data base holds the information about the manufacturer, the product, and the fulfilled UL standards.
maxon specifies for all its assembly partner of controllers that PCBs have to be in use fulfilling the "UL94 V-0" standard. This finally means that all unassembled PCBs which are listed with an "UL File Number" by the controller's "Hardware Reference" fulfill at least the "UL94 V-0" standard.
Some general information about the UL94 standard can be found on the following Wikipedia page:
If specific information related to a concrete "UL File Number" is required, this can be retrieved by the UL data base (and the mentioned link further above).
- The "UL File Number" is just valid for the manufacturer of a PCB and the PCB material. Therefore the "UL File Number" is different depending on the product type (i.e. concrete maxon controller type).
- It is possible that more than one UL file number is listed for a controller by maxon's controller "Hardware Reference". In this case there might be more than one PCB in use (like by the "EPOS4 Compact") or there are different maxon suppliers (= "Second source") of unassembled PCBs defined.
The following documents of this Support Center hold more information concerning UL and standards: