Siemens SIRIUS 3RU2 thermal overload relay
3RU21264DB0 family position
The 3RU21264DB0 belongs to the SIRIUS 3RU2 series of Class 10 thermal overload relays. The "4D" suffix in the MPN designates the 20–25 A sizing band, placing it above 3RU2126 units with "4A/B/C" suffixes and below the "4E/4N" variants.
Factory specifications (3RU21264DB0)
Thermal overload characteristics
| Spec | Value |
|---|
| Accessory type | Thermal Overload Relay |
| Base product number | 3RU2126 |
| Series | SIRIUS 3RU2 |
| Class / trip response | CL10 (Class 10) |
| Current range | 20–25 A |
| Frame size | S0 |
| For use with | Contactors |
Physical and compliance data
| Spec | Value |
|---|
| Package | Bulk |
| Encapsulation | Bulk |
| ROHS | ROHS3 Compliant |
| Product status | Active |
| Mfr | Siemens |
Compare (3RU21264DB0 vs in-family alternates)
Readers must qualify each alternate independently; similarity values derive from catalog-parametric proximity only.
| Spec | 3RU21264DB0 | 3RU21264CB0 | 3RU21264BB0 | 3RU21264AB0 |
|---|
| Current range (A) | 20–25 | 17–22 | 14–20 | 11–16 |
| Series | SIRIUS 3RU2 | SIRIUS 3RU2 | SIRIUS 3RU2 | SIRIUS 3RU2 |
| Frame | S0 | S0 | S0 | S0 |
| Similarity | — | 0.9282 | 0.9282 | 0.9282 |
- 3RU21264CB0 shares the same 3RU2126 base, bulk packaging, and ROHS3 status; differs only in the 4C suffix designating the 17–22 A band.
- 3RU21264BB0 is mechanically and electrically identical except for the 14–20 A trip band encoded by the 4B suffix.
- 3RU21264AB0 matches on frame size, series, and compliance; the 4A suffix calls out the 11–16 A range.
