Pulse Command Mode

Use this when an external controller — a PLC or motion controller — drives the motor directly with pulse signals instead of commanding it over a bus.

Important

Check the drive model number first. Some models have no pulse input pins at all, and no amount of configuration will make them work. See Hardware limits.

Quick answer — what do I set?

You do not calculate anything. Open the drive configuration tool and enter three values.

Enter

Where to find it

Motor encoder type

The letter in the model number on the motor label

Gearbox ratio

Gearbox spec, e.g. 35

Pulse source max frequency

Controller spec, e.g. 50 kHz

To reverse the direction, tick “reverse direction” — no rewiring needed.

Then press “⚡ Write to drive”. The tool reads the current values, shows you old versus new for confirmation, and writes them all in one click.

Tip

The tool handles the drive’s internal register values for you. You never need to know what they are.

What you get

Example: a 50 kHz source with a 35:1 gearbox

Pulses per output revolution

35,000

Maximum output speed

85.7 rpm

Resolution per pulse

0.010 degrees

At the full 50 kHz you reach exactly the motor’s rated speed — it cannot be over-driven.

Top speed depends on the gearbox

Gearbox ratio

Max output speed

Pulses per revolution (at 50 kHz)

35 : 1

85.7 rpm

35,000

20 : 1

150 rpm

20,000

10 : 1

300 rpm

10,000

direct drive

3000 rpm

1,000

Note

A faster pulse source does not make the shaft turn faster. Top speed is fixed by the motor’s rated speed (3000 rpm) divided by the gearbox ratio.

A faster source buys finer resolution — more pulses per revolution.

Do not forget

Setting

Value

Signal format

Match your controller — usually Pulse + Direction

The tool sets everything else. Then press Save and power-cycle the drive, or the values are lost.

How it works (detail)

The pulse count multiplied by the electronic gear ratio gives the motor movement.

pulses × (A ÷ B) = motor movement (inc)

A and B have no factory default — the manual marks them user define because they depend on your motor, gearbox, and pulse source. The drive configuration tool calculates them for you.

Parameters you must set

A — Gear Factor (numerator)

Item

Value

Data type

Integer16 (signed)

Range

−32768 to 32767

Default

none — you must set it

The numerator of the gear ratio. It can be negative, which reverses the direction of rotation without rewiring.

A larger value means the motor travels further per pulse — fewer pulses to send, but coarser resolution.

B — Gear Divider (denominator)

Item

Value

Data type

Unsigned16

Range

1 to 65535

Default

none — you must set it

Warning

Never set this to 0. It is a divisor; zero makes the ratio meaningless.

Usually 1 is enough and you adjust only A. Use B when the ratio you need is not a whole number.

Signal format — PD_CW

How the pulse source is wired. This must match what your controller actually sends — it cannot be calculated, only read from the controller’s datasheet.

Value

Format

Description

0

CW / CCW

Two separate lines, one for each direction

1

Pulse + Direction

One line pulses, one sets direction — most common

2

A / B

Two-phase encoder-style signal

10

422 — two pulse

Differential, better noise immunity

11

422 — Pulse + Direction

12

422 — encoder

Warning

The manual states two different data sizes for this parameter — one chapter says 1 byte, another says 2 bytes.

Always press Read before writing. The drive reports its real size, so you never have to guess.

PD_Filter — input filter

Item

Value

Data type

Unsigned16

Unit

milliseconds

Filters electrical noise on the pulse line. Use it when the cable is long or runs near power wiring.

Setting it too high adds lag — the drive responds later by the amount you set. Start low and increase only if noise persists.

Frequency_Check — frequency ceiling

Item

Value

Data type

Unsigned16

Unit

pulses per millisecond

If the pulse count within 1 ms exceeds this value, the drive raises an over-frequency error.

It stops electrical noise from being counted as real pulses and running the motor away.

Unit conversion: 200 kHz equals 200 pulses/ms. Set it roughly 50% above the frequency you actually use.

Settings that must accompany it

Pulse mode needs more than the parameters above. These two are required.

Operation mode

Set to -4 (pulse train control). Without it the gear ratio you configured has no effect at all.

Other accepted values: 1 position · 3 speed · 4 torque · 6 homing

Controlword

Warning

Pulse mode uses 0x2F, not the 0x0F used by other modes.

With 0x0F the motor never enables — and the usual mistake is to go hunting through the gear ratio settings instead.

Read-only values for diagnosis

Master_Speed

The incoming pulse rate in pulses/ms, before the gear ratio is applied.

Important

This is the first thing to check when the motor does not turn.

Reading 0 means the signal is not reaching the drive at all — the problem is in the cable or the controller. No point investigating gear ratio or signal format.

Slave_Speed

The same rate after the gear ratio is applied.

Compare it against Master_Speed to confirm the ratio behaves as intended.

Hardware limits

Manual specification

Maximum pulse input frequency

below 500 kHz

Input voltage

3.3 – 24 V

Ordinary DIN pins (IN1–IN4)

below 1 kHz — cannot accept pulses

Motor rated speed

3000 rpm (the 30 in the model number)

Warning

Some drive models have no pulse input.

The manual notes that certain models ending in C and E accept 24V logic power but do not support the pulse input function — no configuration will make them work.

Read the full model number from the drive label before you begin.

Do not design for the full 500 kHz

500 kHz is what the drive can accept, not what you should run.

  • The manual says “below 500 kHz”, not “up to”

  • Your pulse source is usually the bottleneck first — typical open-collector outputs stop around 100 kHz

  • Higher frequencies demand shorter cables and differential signalling

Design for 100–200 kHz and use the A value to bring the frequency down.

Worth knowing

Note

The gearbox ratio does not affect the frequency limit.

Pulses drive the motor itself; the gearbox sits downstream. It only changes how many pulses make one output-shaft revolution and the maximum output speed — it does not let you send pulses more slowly.

Encoder resolution changes everything

The counts per motor revolution depend on the encoder fitted to your motor, identified by a letter in the model number.

Letter

Encoder type

Counts per revolution

A

2500 PPR incremental

10,000

M

16-bit magnetoelectric

65,536

K

16-bit absolute

65,536

A 6.5× difference. Get this wrong and every ratio derived from it is wrong. Read it from the motor label — the drive does not expose this value.