Siemens LD63B300 Molded Case Circuit Breaker
- 300A
- 3 Pole
- Unit Mount
Quantity
Siemens LD63B300 - 300A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
Description
Engineered for commercial and industrial facilities, this 300-amp, three-pole Siemens MCCB ensures safe and efficient low-voltage power distribution. This bolt-on breaker is fully compatible with Siemens Sentron panelboards and standalone enclosures. Facility managers can also use it to replace legacy ITE LD3300 units. It features a thermal-magnetic trip mechanism with long-time and instantaneous (LI) functions. The breaker includes an interchangeable trip unit and is HACR rated.Specifications
| Brand | Siemens |
|---|---|
| Series | LD6 |
| Amperage | 300A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 600VAC, 500VDC |
| Phase | 3 |
| AIC Rating | 65kA @ 240VAC, 35kA @ 480VAC, 25kA @ 600VAC, 25kA @ 500VDC |
| Frame Type | LD |
|---|---|
| Terminal Type | Lugs |
| For Use With | Siemens Sentron Panelboards (Type S1, S2, SE), Switchboards, Enclosures |
| Wire Gauge | (2) 3/0 AWG-500 kcmil (Cu/Al) |
| Max Wire | 500 kcmil |
| Min Wire | 3/0 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Adjustable Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch |
|---|---|
| Accessories | Line and Load Lugs (TA2J6500) |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CSA, HACR, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Interchangeable Trip Unit, Reverse Feed |
Product FAQs
6 answersWhich panelboards are compatible with the Siemens LD63B300?
This LD frame breaker is designed for installation in Siemens Sentron Type S1, S2, and SE panelboards, as well as compatible Siemens switchboards and standalone enclosures.
What is the adjustable magnetic trip range for the LD63B300?
The instantaneous magnetic trip unit on this 300A breaker can be adjusted between 1250A and 2500A to coordinate with downstream loads and prevent nuisance tripping.
What are the wire size limits for the standard lugs on this breaker?
The factory lugs accommodate two conductors per phase, accepting wire sizes from 3/0 AWG up to 500 kcmil for both copper and aluminum conductors.
Is the LD63B300 rated for direct current (DC) systems?
Yes, in addition to its AC ratings, this thermal magnetic breaker is rated for 500VDC applications with a 25kAIC interrupting capacity.
How does the LI trip unit function on the LD63B300?
The thermal magnetic trip unit provides fixed long-time (L) protection for sustained overloads and adjustable instantaneous (I) protection for short circuits.
How does the LD63B300 mount into a panelboard?
As a unit mount, bolt-on breaker, it fastens directly to the bus of compatible Sentron panelboards and switchboards. Specific strap kits or mounting hardware may be required depending on your exact panelboard configuration.
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