Wireless industrial crane control panels | remote control systems

Wireless crane remote controls – an engineer’s way to choose

A radio remote replaces the buttons of a wired pendant, but the crane is still switched by contactors. That is why the remote is chosen in the same order as the control circuit is designed: 1) motions and speeds → number of receiver outputs, 2) control circuit voltage → receiver supply, 3) safety circuit – STOP, START, loss of link, 4) radio frequency, range and how many cranes work in one area, 5) environment – IP rating. Only then the specific model.

Schematic diagram: receiver relays switch contactor coils, STOP de-energises main contactor KM0. Click to enlarge.

⚡ 3. Safety circuit – STOP, START and loss of link

In wireless control, safety comes not from the button itself but from how the receiver outputs are wired into the circuit. The main contactor (MAIN) must be in series with all motions.

⚡ Requirements for the electrical equipment of hoisting machines (EN 60204-32) for cableless control: on loss of the link the crane must stop automatically, and STOP must de-energise the main contactor. This is tested every time a receiver is installed or replaced.

4. Radio link – frequency, range, several cranes

Frequency and operating range depend on the remote series. The manufacturer’s range is given for open space – in a production hall with metal structures it is shorter.

• Several cranes in one area – each transmitter–receiver pair must have a different address code; with many remotes, use different channels as well.
• Antenna – mount the receiver or its antenna so that the metal cabinet and structures do not block the signal.
• Interference – keep the receiver and its wiring away from frequency inverters and power cables.
• Batteries – the transmitter is battery powered; a flat battery shortens the range, so replace batteries in time.

⚠ In the EU, short-range radio devices mostly use the 433 MHz and 868 MHz bands. For 315 MHz models, check before use that the frequency is permitted in your country.

5. Environment – transmitter IP rating

The first digit of the IP code indicates protection against dust, the second against water. All transmitters in this group are dust-tight (6); they differ in water protection.

⚠ The IP rating applies only with the battery cover tightly closed and an undamaged gasket. The receiver is usually mounted in a cabinet or has its own enclosure IP – check it separately.

⚡ Safe installation and commissioning

• ⚡ The receiver must be wired into the crane circuit by a competent electrician, with the power switched off and absence of voltage verified.
• The receiver supply is taken from the control circuit and protected according to the manufacturer’s instructions.
• The MAIN output is wired in series with the main contactor coil; the direction contactors are interlocked with NC contacts.
• Limit switches and overload limiters remain in operation – do not bypass them.
• Follow the requirements for electrical equipment of hoisting machines (EN 60204-32) and the applicable lifting equipment maintenance rules.

Commissioning test – without load:

1. Each button moves the crane in the direction marked on the remote.
2. STOP stops all motions; after releasing STOP the crane does not start without START.
3. During a motion, switch the transmitter off or remove the batteries – the crane must stop.
4. Limit switches operate in both directions.
5. With several cranes in the hall – each remote controls only its own crane.

LOTO – before crane and hoist maintenance

A switched-off transmitter, a pressed STOP or a removed key is not safe energy isolation. The receiver, contactors, motor and brake remain live.

1. Stop the crane and lower the load.
2. Switch off the crane main (incoming) switch.
3. Lock it with a personal LOTO padlock and attach a warning tag; when several people work – use a multi-lock hasp.
4. Verify absence of voltage, and only then start work.

Padlocks, hasps and tags – LOTO lockout devices. Other equipment – work safety.

In short

• Directions and speeds determine the number of buttons and receiver outputs.
• Receiver supply = contactor coil voltage; the relays switch coils, not the motor.
• STOP and loss of link must de-energise the main contactor – test at commissioning.
• 868 MHz – up to 250 m, 433 MHz – up to 100 m; several cranes – different codes.
• For maintenance – lock the main switch with a LOTO padlock.

Tell us the crane type, directions and speeds, the contactor coil voltage and, if possible, send a photo of the circuit – we will select the remote, receiver and contactors. Contact us.