50 mm Encoder with 8 mm Shaft: The VXT-E50S08 Totem Pole Series

When a machine needs a sturdier shaft, a larger bearing span and an output that works with almost any controller, the 50 mm encoder with an 8 mm shaft is the standard choice. The VXT-E50S08 series pairs this robust size with a totem pole (push-pull) output, which connects to both NPN-type and PNP-type PLC inputs. That makes it one of the most versatile encoders you can stock.

The VXT-E50S08 range

Model	Resolution	Output	Supply	Channels
VXT-E50S08-1000-T	1000 PPR	Totem pole (push-pull)	8–26 V DC	A, B, Z
VXT-E50S08-1024-T	1024 PPR	Totem pole (push-pull)	8–26 V DC	A, B, Z
VXT-E50S08-2500-T	2500 PPR	Totem pole (push-pull)	8–26 V DC	A, B, Z

Common specifications: ø50 mm housing, ø8 mm g6 solid shaft with a flat, ø30 mm spigot, three M4 mounting holes on a ø40 mm pitch circle, 2 m shielded radial cable, response frequency up to 300 kHz, 6000 rpm mechanical speed, IP54, −20 to +85 °C.

Why a totem pole output?

A totem pole output has two transistors: one drives the signal high and one drives it low. The result is a clean, actively driven square wave in both directions. In practical terms:

• It works with NPN-type and PNP-type inputs, so one encoder model covers machines built for different controllers.
• Edges are faster and cleaner than with an open collector and a weak pull-up, which helps at higher pulse rates.
• No external pull-up resistor is needed in most installations.

For OEMs supplying machines to customers with different PLC brands, standardising on a totem pole encoder reduces the number of spares to stock.

Choosing between 1000, 1024 and 2500 PPR

• VXT-E50S08-1000-T: 1000 PPR makes decimal calculations easy. With a 100 mm circumference measuring wheel, every pulse is 0.1 mm.
• VXT-E50S08-1024-T: 1024 PPR is a binary-friendly value used by many drives, motion modules and existing machine programs. Choose it when replacing an existing 1024 PPR encoder so no scaling changes are needed.
• VXT-E50S08-2500-T: 2500 PPR gives finer resolution for print registration, cut-to-length accuracy and slow-speed position control. At the 300 kHz response limit it supports up to 7200 rpm electrically, so the 6000 rpm mechanical limit still applies.

An alternative to Autonics E50S8 and Omron 50 mm encoders

The Autonics E50S8 series is one of the most widely used 50 mm, 8 mm shaft encoders in India, and its totem pole versions carry a "T" in the model code, for example E50S8-1000-3-T-24. Omron offers 50 mm encoders in the E6C2-C and E6C3-C families. If you are looking for an equivalent:

If you use	Consider
Autonics E50S8-1000-3-T-24	VXT-E50S08-1000-T
Autonics E50S8-1024-3-T-24	VXT-E50S08-1024-T
Autonics E50S8-2500-3-T-24	VXT-E50S08-2500-T
Omron 50 mm encoder, 8 mm shaft	VXT-E50S08 model with matching PPR (check the output type)

Before replacing, compare the mounting hole pattern, spigot diameter and cable exit direction with your existing installation. Published data for the Autonics E50S series lists a maximum of 5000 rpm; VXT-E50S08 is rated to 6000 rpm mechanically. Both support response frequencies up to 300 kHz.

Where the VXT-E50S08 fits best

• Printing and converting: web speed, print registration and sheet counting on flexo, offset and rotogravure lines.
• Cut-to-length lines: steel coil, paper, film and corrugated board, using a measuring wheel on the material.
• Conveyors and material handling: belt speed, tracking and synchronisation.
• Textile machinery: fabric length on stenters, inspection machines and folding machines.
• Packaging machines: form-fill-seal, carton erectors and labellers.
• Wire and cable: length counting on take-up and coiling machines.

Installation tips

• Use a flexible coupling and keep shaft loads within 30 N radial and 20 N axial.
• For measuring-wheel applications, mount the encoder on a spring-loaded arm so the wheel keeps constant contact without overloading the shaft.
• Route the encoder cable separately from motor and inverter cables, and earth the shield at the controller end.

Frequently Asked Questions

What is a totem pole encoder?

A totem pole (push-pull) encoder drives its output actively both high and low. It can be connected to PLC inputs configured for NPN sensors or for PNP sensors, which makes it more flexible than an open collector encoder.

Can I use VXT-E50S08-1024-T with a Delta, Mitsubishi or Siemens PLC?

Yes, as long as the PLC high-speed counter input accepts 24 V signals at your pulse rate. The totem pole output works with both NPN and PNP input configurations.

Is VXT-E50S08 a replacement for Autonics E50S8?

It is in the same 50 mm, 8 mm shaft class with an equivalent totem pole output. Check the mounting holes and cable direction, or share your Autonics model number and we will confirm the closest match.

What is the maximum speed of the VXT-E50S08-2500-T?

The mechanical limit is 6000 rpm. At 2500 PPR and the 300 kHz response limit, the electrical limit is 7200 rpm, so 6000 rpm is the operating limit.

Order the VXT-E50S08 series

Contact us with the PPR and quantity you need, or the model you want to replace. We supply VXT encoders across India with datasheets, wiring support and a 1-year warranty.

Autonics and Omron are trademarks of their respective owners. They are mentioned for comparison and cross-reference only; VXT is not affiliated with these companies.