Download What is `duty cycle` for an electric gate operator

What is ‘duty cycle’ for an electric gate operator?
The duty cycle for an automated gate operator is in basic terms the number of times the gate
can open and close without overheating and is normally expressed in a percentage.
For example, if you have a gate operator which has a 50 % duty cycle, it basically means if
the gate operator drives the gate open and it takes 30 seconds to do so, it then should ‘rest’
for another 30 seconds before it opens the gate again.
If it doesn’t ‘rest’ for that time period there is a likelihood that the gate operator will eventually
stop due to the motor being overheated
What happens if the gate does need to open and close constantly ?
‘Gate Drive Systems Australia’ is an Australian manufacturer of automatic gate operators and
their range of variable speed and low voltage gate operators all have a 100 % duty cycle.
This means the gates can open and close all day long if necessary and still not overheat.
This feature is essential for any premises which require the gates to be closed for security
reasons but also need to the gates to be opened and closed frequently due to a need for
many vehicles to enter and exit.
If the gates are used a lot, will the automatic gate drive system wear out faster?
‘Gate Drive Systems Australia’ are to their knowledge, the only gate operator manufacturer
which exclusively uses Industrial cast iron gearboxes, these gearboxes are designed and
used in heavy intensive applications such as conveyor systems and applications where they
may be running at full capacity for 12 hour periods.
Needless to say then, the application where they are used to open and close a gate, has no
where near the load placed onto the gearbox so they will last 20 + years.
Similarly, the motors we use for our variable speed inverter driven operators are 3 phase
induction motors, these motors are maintenance free as there are no brushes to wear, simply
a stator winding with a rotor which turns due to the ‘induction’ affect of the magnetic fields on
the rotor.
If the motors on the variable speed drives gate operators are 3 phase, do you need a 3 phase
power supply?
No! The motors are a 3 phase motor but ‘Gate Drive Systems Australia’ uses invertors to
drive these motors. So only a single phase supply is required for all GDS gate operators; this
single phase 240 V supply feeds the inverter, the inverter then converts the single phase
supply to basically 3 phase supply to power the motor.
The inverter also varies the frequency output, frequency is proportional to motor speed which
is therefore proportional to the speed of the gate.
Therefore, by varying the frequency ramp up time, the frequency the inverter puts out when
opening and closing and the frequency ramp down time, we are able to have complete control
over the gate operating characteristics and speeds of the gate.