Description
Product Overview
The Allen-Bradley 81001-340-71-R is a legacy power-electronics component associated with Allen-Bradley industrial drive systems. Available industrial parts references identify the exact part number as a thyristor module, while related 81001-series numbers are cataloged as drive boards and power-electronics components. Its function belongs to the high-power section of a motor-drive assembly rather than the PLC control layer: semiconductor switching devices handle the conversion and regulation of electrical power supplied to the drive’s motor circuit.
For Allen-Bradley 81001-340-71-R, the suffix should be treated as part of the complete identification. This is important with older drive hardware because visually similar power modules can use different semiconductor ratings, gate-drive arrangements, mechanical mounting, or electrical interfaces. The available records also associate 81001-340-71-R with other Allen-Bradley drive components such as 80190-220-01-R and 80190-219-01G, indicating that the component should be evaluated within its original drive assembly rather than treated as a generic thyristor replacement.
The Allen-Bradley 81001-340-71-R is therefore most relevant to maintenance teams keeping an older high-power drive in service. A correct replacement can avoid unnecessary changes to the existing power section, but semiconductor matching is critical. To be completely transparent, publicly available documentation for this exact legacy part number does not provide enough reliable information to publish a specific voltage, current, gate-trigger, or thermal rating without risking an incorrect specification.
Product Introduction
A failed power semiconductor can stop a large motor drive even when the control electronics remain fully operational. 81001-340-71-R is identified as an Allen-Bradley thyristor module used in legacy drive power electronics.
For a legacy Allen-Bradley drive replacement, matching the exact part number and physical/electrical configuration is more important than selecting a module based only on apparent semiconductor size or voltage class.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Manufacturer | Allen-Bradley |
| Part Number | 81001-340-71-R |
| Product Type | Thyristor Module / Drive Power Electronics |
| Functional Category | High-Power Drive Component |
| Primary Application | Industrial Motor Drive |
| Semiconductor Technology | Thyristor |
| Installation | Internal drive power assembly |
| System Layer | Power Conversion |
| Control System Role | Motor-power switching rather than PLC logic execution |
| Related Part Family | 81001-series drive/power components |
| Exact Voltage Rating | Requires nameplate/datasheet verification |
| Exact Current Rating | Requires nameplate/datasheet verification |
| Gate-Drive Specification | Requires assembly-specific verification |
| Thermal Rating | Requires assembly-specific verification |
| Condition | New Surplus / Legacy Spare |
The available references consistently identify 81001-340-71-R with Allen-Bradley and drive power/thyristor hardware, but they do not establish sufficiently reliable exact electrical ratings for this particular suffix.
Related Products
- 80190-220-01-R — Related Allen-Bradley drive power component frequently listed alongside 81001-340-71-R. It belongs to the same legacy drive spare-parts environment but should not be substituted without electrical verification.
- 80190-219-01G — Related drive board associated with the same legacy power-electronics assemblies. Its board-level function differs from the thyristor module.
- 81007-465-51-R — Allen-Bradley drive board used in related legacy drive hardware. It is a board-level component rather than a direct thyristor-module replacement.
- 81001-354-71-R — Related 81001-series Allen-Bradley power component. Similar numbering does not establish interchangeability.
- 81001-355-71 — Another related Allen-Bradley 81001-series component found in legacy drive spare-parts records. Application and electrical ratings must be checked before considering substitution.
- 81001-340-73-R — Closely numbered 81001-series component. The different suffix should be treated as a separate configuration until the original drive documentation confirms equivalence.
81001-340-71-R
Frequently Asked Questions
What is Allen-Bradley 81001-340-71-R used for?
The 81001-340-71-R is a thyristor power module used within legacy industrial drive equipment.
Its function is associated with the power-conversion section of the drive, where semiconductor switching controls electrical energy delivered through the motor-power circuit. It is not a PLC CPU, standard I/O module, or communication card.
Is 81001-340-71-R a PLC module?
No.
Available records identify it as a drive power/thyristor component.
The distinction is important during troubleshooting. If the motor drive has lost output power, this type of component should be investigated alongside the firing circuit, gate-drive circuitry, DC bus, snubber components, cooling system, and associated power boards.
What voltage and current does 81001-340-71-R support?
I would not publish a specific voltage or current rating without the original drive documentation or component nameplate.
Legacy power modules can have closely related part numbers while carrying different semiconductor ratings. Guessing a current or voltage value from the 81001 series could result in an incorrect replacement.
For procurement, provide the complete drive model and the existing module photographs when the electrical rating is not documented.
Can I replace 81001-340-71-R with another 81001-series module?
Not automatically.
A proper substitution review should compare:
- Semiconductor type
- Voltage rating
- Current rating
- Gate-trigger characteristics
- Mounting dimensions
- Terminal configuration
- Heat-sink arrangement
- Gate-driver compatibility
- Original drive model
- Hardware revision
The 81001-340-71-R should therefore be treated as an exact replacement part unless engineering documentation confirms another suffix as an approved alternative.
Can I hot-swap this module?
No.
This is power-conversion hardware, not a typical live-replaceable PLC I/O module. The associated drive must be safely isolated, discharged, and verified de-energized before accessing the power section.
Particular attention should be paid to stored DC-bus energy. A visual indication that the drive is powered down is not sufficient for maintenance authorization.
Will replacing the thyristor module restore the drive automatically?
Not necessarily.
A failed thyristor may be the result rather than the original cause of a drive failure. Before installing the replacement, check for:
- Shorted or failed companion semiconductors.
- Gate-drive faults.
- DC-bus abnormalities.
- Snubber-network damage.
- Cooling problems.
- Excessive motor current.
- Motor insulation faults.
- Damaged power-board traces.
- Incorrect firing signals.
Replacing the semiconductor without addressing the initiating fault can result in another immediate failure.
How should a New Surplus 81001-340-71-R be tested?
For this type of component, acceptance testing should be more rigorous than a simple visual inspection.
Recommended procedure:
- Verify the complete 81001-340-71-R marking.
- Compare mechanical dimensions with the removed unit.
- Inspect terminals, semiconductor housing, and mounting surfaces.
- Check for cracks, corrosion, contamination, or heat discoloration.
- Verify semiconductor electrical characteristics against the original drive documentation.
- Inspect gate and auxiliary terminals.
- Confirm the associated gate-drive circuit before energizing.
- Perform controlled power-up with appropriate current protection.
- Monitor drive output and semiconductor temperature.
- Record the test results.
Because publicly indexed technical data for this exact legacy part is limited, a unit should not be accepted solely because its physical appearance matches the old module. The drive model, original module markings, and electrical test results should be used to establish compatibility.
