1900 electrical box
The analysis of **“1900 Electrical Box”** is as follows, and it is necessary to make inferences by combining industry terms
and common naming rules:
I. Possible Meanings of "1900"
"1900" usually **does not directly refer to the size** (since the conventional sizes of electrical boxes are in inches or millimeters,
such as "4x4x2" inches), and it is more likely to be one of the following two situations:
1. Model/Series Number (Most Common)
Many brands use **series numbers** to name electrical boxes. For example:
- **Thomas & Betts 1900 Series**:
- **Type**: Metal Junction Box, which supports cable connections.
- **Features**:
- Made of cold-rolled steel with a galvanized anti-corrosion surface;
- Standard knockouts are equipped, suitable for 1/2"~1" conduits;
- Complies with NEC 314.16 (capacity calculation) and UL 514A certification.
- **Common Sizes**:
- 1900-4: 4x4x1.5 inches (suitable for residential lighting circuits);
- 1900-6: 6x6x2.5 inches (suitable for multi-core cables or industrial scenarios).
2. Volume Code (Rare)
In extremely rare cases, "1900" may refer to the **internal volume** (in cubic inches), and the corresponding size needs to
be calculated through the formula:
**Volume = Length × Width × Depth**
Example: If the volume is 1900 in³, the possible size is **14×14×10 inches** (commonly seen in large industrial junction boxes).
II. Distinction from "Pull Box"
| Characteristics | Junction Box (such as the 1900 Series) | Pull Box |
| Allowable Joints | Yes | No |
| Minimum Depth | 1.5~3 inches | ≥6 inches (to meet the cable bending radius) |
| Typical Applications | Connection of lamps and sockets | Long-distance cable threading and turning |
III. Core Parameters of the 1900 Series Electrical Box (Taking Thomas & Betts as an Example)
| Parameters | Details |
| Material | Galvanized steel (stainless steel is optional) |
| Protection Rating | IP40 for indoor use, and IP66 is optional for the waterproof type (a sealing rubber ring is required) |
| Knockouts | Multiple standard holes (1/2", 3/4", 1") are pre-set at the top/bottom |
| Grounding | Built-in grounding terminals, and the PE wire needs to be connected |
| Applicable Scenarios | Branches of residential switches, sockets, and distribution boxes; lighting systems in commercial buildings |
IV. Precautions for Purchase and Installation
1. **Confirm the Purpose**:
- If it is used for **cable connections**, select a junction box (such as the 1900 series);
- If it is used for **threading/turning**, a **Pull Box** needs to be selected (larger in size and without the connection function).
2. **Capacity Calculation (NEC 314.16)**:
- Capacity of a single conductor: A 12 AWG wire occupies 2.25 in³, and a 10 AWG wire occupies 3 in³;
- The 1900-4 type (4x4x1.5 inches, with a volume of 24 in³) can accommodate at most **10 12 AWG wires**.
3. **Chinese Alternative Solutions**:
- Domestic brands such as **Chint** and **Delixi** have products of similar specifications, which need to comply with
the **CCC certification** and the GB 7251 standard.
V. Common Misunderstandings and Clarifications
- **Misunderstanding**: Thinking that "1900" is a size (such as 1900mm).
**Clarification**: The sizes of electrical boxes are usually in inches. 1900mm (1.9 meters) is far beyond the normal range
(the largest common size is 600mm).
- **Misunderstanding**: Confusing the functions of junction boxes and pull boxes.
**Clarification**: Pull boxes cannot be used for cable termination, and they need to be distinguished by model suffixes
(such as "-PB").
Conclusion
"1900 Electrical Box" most likely refers to the **Thomas & Betts 1900 Series Junction Box**, which is used for cable connections
and branches. The size and type need to be selected according to the actual scenario. If it involves a **Pull Box**, the purpose
needs to be clarified and the pull box standards (such as NEC 314.28) need to be referred to.
