RPM and SPM Tachometer Generators

Rugged and dependable generators measure and display RPM of any rotating object

Forum RPM and SPM Tachometer Generators are available in explosion-proof and non-explosion-proof models. Each generator has an output of 10 VAC @ 1,000 RPM in either direction — clockwise or counterclockwise.

  • Non-Explosion proof (A78-145-1A)
  • Explosion-proof model (A75-1163)



  • 10 VAC @ 1,000 RPM output
  • Explosion-proof model is listed by Underwriter’s Laboratories (UL)for use in hazardous locations, Division 1, Group D (natural gas or the vapors from lacquer solvents, acetone, alcohols, and petroleum derivatives such as gasoline) and Class 2, Groups F and G
  • Easily mounted, with a direct connection to the pump pinion shaft by means of a flexible coupling or by a V-belt connection between the shaft and the generator pulley
  • A heavy-duty, oil-resistant electrical cord connects the generator to the RPM meter
  • Generator supplies all the power necessary for one or more Indicators — no outside power or batteries are required


  • Center-point mounted drums ensure optimum accuracy
  • Smooth, machine-grooved drum surface extends cable life
  • Heavy-duty, high-grade structural steel construction with tapered roller anti-friction bearings and heat-treated alloy shaft provides a super strong anchor with exceptional durability
  • Proof-testing to 150% of rated capacity ensures superior reliability
  • Durable bronze wireline clamp inserts provide tight cable grip without damage to the line
  • Easy to install and service.