Find the right counters & tachometers in Johannesburg
When a project or production line needs accurate RPM or event counting, waiting weeks for parts is not an option. Communica stocks a wide practical selection of panel counters, handheld tachometers, optical pickups and digital frequency counters so Johannesburg-based makers, students and engineers can keep prototypes and repairs on schedule. We prioritise local availability, quick branch collection, and VAT invoicing for education and procurement workflows.
Why buy locally from Communica in Johannesburg
Local stock reduces lead times for urgent repairs and lab work. Collect from our Samrand head office or arrange a branch pickup near Pretoria or Cape Town; check branch hours and collection options before you travel. Our teams can advise on input types (pulse, TTL, open-collector), mounting formats (panel cut-out sizes) and compatible accessories like optical targets, reflective tapes and shielded cable for pickup sensors.
Common specification callouts to compare
Compare devices by measurement range, input type, resolution and display. Below is a concise spec table to use when comparing models - these are the practical attributes that determine fit for a job, not marketing claims.
| Spec | What it means | Practical selection hint |
|---|---|---|
| Measurement range | RPM or frequency span a device reads | Choose a tachometer with headroom above expected max RPM |
| Input type | Optical, magnetic pickup, TTL pulse, AC pickup | Match to sensor on your motor or add an appropriate pickup accessory |
| Resolution & sample time | How stable the reading is and update speed | For control loops prefer faster sample times |
| Display & mounting | Panel mount, handheld or DIN rail | Panel cut-out dims matter for retrofits |
Simple compatibility checklist
- Confirm input: is the source TTL, hall-effect, or optical?-if unsure, bring a sample or photo to a branch.
- Decide mounting: handheld for field checks, panel counters for permanent machines, DIN counters for control cabinets.
- Power: 12-24 V DC is common for industrial modules; handhelds often run on batteries.
Before you buy, view our product categories to shortlist options and check stock status: All Products. For a quick overview of Communica and our service ethos, see our about page: About Us.
Example wiring and a quick calculation
Many tachometers convert pulses to RPM with simple math. If a sensor generates N pulses per revolution, and you measure pulse frequency f (Hz), then RPM = (60 * f) / N. For a single-pulse-per-rev encoder, RPM = 60 * f.
Optical pickup wiring (simple ASCII):- sensor -----[ shielded cable ]----- tachometer input +V --------------+ +V (if active) GND -------------+-------------------- GND Output -----------> tachometer pulse input
For hands-on support and stock checks, look through our all products index and confirm local availability: All Products.
