Difference between VF4-15F11-S05 and C05

What the difference between a Potter Brumfeld relay VF4-15F11-S05 and C05? Will the C05 work in and fit the same?


The only difference I see is the coil resistance values.
VF4-15F11-C05 = 79.5Ω
VF4-15F11-S05 = 90Ω
Per the drawings from the manufacturer.
VF4-15F11-C05 Drawing
VF4-15F11-S05 Drawing

Per the datasheet, the -C05 variant appears to lack coil suppression and have a sealed cover, whereas the -S05 contains an integral suppression diode and has a standard cover.

Because of this difference, there is a fair chance that blindly swapping a -C05 for an -S05 will result in lack of function or damage to the equipment in which the relay is installed. The adaptations to accommodate such a change are not severe, but they do require a bit of care.

Hi @rick_1976

You mentioned in your reply that there may be potential issues using a vf4-15f11-c05 relay in place of a vf4-15f11-s08. Does the same hold true if a vf4-15f11-s08 were substituted for a vf4-15f11-c05?


I’m not seeing that vf4-15f11-s08 is a valid part number based on the listings; you might want to double-check your part number.

That said the suffix would appear to call out a 2.7K parallel suppression resistor. That’s a fairly benign difference compared to the non-suppressed -C05, and I would not expect it to be problematic in most cases. No guarantees though.

Good catch. The part # is actually VF4-11H11-S08. Didn’t notice that before.
So the question is can i safely use a VF4-11H11-S08 relay instead of the vf4-15h11-c05?
Thank you for your insight. I understand this is a non-binding opinion.

That would seem like a fairly safe substitution, yes.

Thank you Rick. I really appreciate it.