Quick Answer:The Reversing Key | Commutator (Pohl’s commutator) is a double-pole double-throw switch with brass strips and cross-linked bridges that reverses the direction of current in a circuit without disconnecting any leads.
Last updated: 18 October 2026
Key Features
Double-pole double-throw (DPDT) commutator.
Heavy-duty brass strips and bridge links.
Four connection terminals.
Pre-wired cross-links reverse the current instantly.
Technical Specifications
Specification
Value
Switch type
DPDT commutator
Contacts
Heavy-duty brass strips and bridge links
Terminals
Four
Wiring
Pre-configured cross-linkages for current reversal
How It Is Used
The supply is connected to one pair of terminals and the load, such as a tangent galvanometer coil, to the other. Changing the switch position reverses the current through the load, so readings can be taken for both directions and averaged, as in tangent galvanometer and induction experiments.
Frequently Asked Questions
Why use the Reversing Key | Commutator with a tangent galvanometer?
It reverses the current direction instantly without disconnecting leads, so deflections can be read for both directions of current.
