Selection reference
| Component | What it changes | When it is needed |
|---|---|---|
| Flatwise elbow | Direction in one plane | The route turns in that plane |
| Edgewise elbow | Direction in the other plane | The route changes level or orientation as drawn |
| Combination elbow | Two bends in one piece | An obstacle must be bypassed |
| Transposition joint | Phase sequence | Required bar order differs between the ends |
Source: LVA manual §5.3, §5.6 and §5.9.3.
The documented minimum transposition-joint length is 1500 mm; the phase sequence at both ends is agreed with the customer.
Do not apply this dimension to GM or Data Pro.
More suitable if…
It is more suitable if you define route bends and equipment phase order separately before manufacturing the components.
Not ideal if…
It is not ideal to order transposition for a simple direction change: it adds a function the route may not need.
Frequently asked questions
Does every elbow change the phase sequence?
No; an elbow handles geometry, whereas a transposition joint changes the phase sequence.
What should you specify for transposition?
The required phase order at each end, connection drawings for both pieces of equipment, model and current.
Is a combination elbow a transposition unit?
No; the manual describes two bends, identical or mixed, to bypass obstacles.
Can LVA elbow dimensions be used for GM or Data Pro?
No; each system has its own documented components and dimensions.
From drawing to estimate
Selecting the correct fitting from the drawing avoids rework and makes a fair installed-cost comparison against cable bends and terminations.