By: Robert Toy
Robert works for PTI Security Systems in the Engineering Department, and has worked in the self-storage security industry for over 25 years.
When it comes to security for your self-storage facility, your gate is an extremely important component. You’re expecting it to work 24 / 365 to allow your customers in, and to keep dangerous people out. If your gate is broken, then your security suffers. To help keep your gate from causing you headaches, it’s a great idea to perform preventative maintenance on the operator and gate.
A couple of notes first. Most importantly, maintenance on gates and operators should be done by trained professionals only. Gate operators can be hazardous and cause harm or even death if you are not careful, and as such this list is intended for informational purposes only. The other is that operator manufacturers will have their own suggestions for maintenance and may have a more frequent schedule than what is shown below, or include extra items. Always defer to their instructions.
There are four types of gates and operators:
- Slide Gates. These can be “Cantilever” types that have rollers mounted on posts and a counter-balance, or “Track” types that have rollers that run on an upside down “V” track that is set into the ground. Slide gates can be driven by either a chain or hydraulic rollers that pinch a track attached to the gate.
- Barrier Arm Gates with wooden, composite, or aluminum arms.
- Vertical Lift Gates.
- Swing Gates.
- Lubricate the chain with lightweight chain oil. Do not use WD-40.
- If applicable, check to make sure the V-track or hydraulic track is clear of debris.
- Inspect any rollers for wear or damage.
- Lubricate rollers as needed.
Vertical Lift Gates
- If the operator has a battery backup and is not a sealed type, check the water levels.
- Lubricate hinges.
All Gate Types
- Check vehicle detection loops (See below).
- Clear and cut any vegetation that is near any moving parts of the operator or gate.
- Adjust the chain (if applicable). You should have about 1” of chain “sag” for every 10 feet of length, but no more than 3”.
- If the gate has hydraulic rollers, make sure they are in good condition, and that there are no leaks from the hydraulic system.
Vertical Lift Gates and Barrier Arm Gates
- Check belts (if applicable) for wear and tension.
- If the gate has a clutch, make sure it is adjusted to the proper tension.
- Check any hardware holding the gate to the operator, and tighten as needed.
All Gate Types
- Check mounting hardware holding the gate operator to the pad, and tighten if needed.
- Test any reversing safety devices that the operator is equipped with. This may be an “overload” type of detection or a safety edge attached to the side or bottom of the gate itself (See below).
- If the operator has a “gear reducer” that uses oil, then check the level and refill as needed with the specified type.
- Check that the operator stops the gate at the proper position both when opening and closing. The gate should not “bang” into its catch forks or rest stop, but should smoothly stop as they meet. Adjust any limit devices in the operator to achieve this smooth stop.
Every 6 months:
For all types of operators, you should check the “smoothness” or “balance” of the gate. How easy is it to push open and closed with the drive mechanism (chain, belt, etc.) disconnected? Does the gate open and close without binding or jerking? If it’s a barrier or lift gate, does the lift arm move up and down freely with the clutch disengaged? Do swing gates move freely on their hinges?
A gate that is difficult to open and close will put a lot more stress on the operator, and will cause premature wear and failure.
Testing Vehicle Safety Loops / Electric Eyes
Safety devices that are intended to prevent your gate from closing on a vehicle are very important part of your gate system. These devices will either be a vehicle detection “loop,” or an electric eye. Personally, I recommend a loop even if the operator is equipped with an eye. An eye has a limited capability in that, the vehicle must be in the path of the gate to be detected. Unlike an electric eye, a loop will detect a vehicle a few feet from the gate, and can react more quickly.
A common misconception with safety loops is that they work by detecting weight. They actually work by detecting ferrous metals—iron and steel. They will not detect non-ferrous metal, like aluminum.
Test safety loops by driving a vehicle onto the loop (but not into the path of the gate) while the gate is closing. The gate should stop. Depending on the operator, it may reverse back to the open position. While you are testing, keep an eye on the loop wires. Make sure they are not becoming exposed due to loss of the filler material that covers the “slot” in the asphalt or concrete. Patch as needed.
Test electric eyes by covering the eye with a piece of cardboard as the gate is closing. Again, the gate should stop, and possibly re-open depending on type. Make sure that all hardware holding the eyes in position is secure.
Generally, safety loops and eyes should hold the gate open as long as a vehicle is on the loop, or the eye is being blocked. They should not “time out” and allow the gate to close while an obstruction is still present.
Testing Entrapment Detection Devices
Gate operators and their attached gates have caused serious injury and death in the past. To reduce the possibility of this happening, gate operators now have entrapment detection built into them as well as the capability to attach external detection devices. The detection devices should be tested to ensure that they are operating properly.
Remember, no system is perfect and you should always stay clear when the gate is in operation. These gates are not meant for pedestrian traffic, and a separate walk through gate should be provided.
Overload Detection: This type of detection uses the “current draw” of the gate motor to detect entrapment. The safety circuit senses a “spike” in the current going to the gate motor. If this spike exceeds a pre-set value, then the gate is supposed to stop, reverse a short distance, and then stop again. Some operators are equipped with an audible alert that will also be triggered, and may require a manual reset button be pressed before resuming normal operation.
To test this, a technician will operate the gate so that it is moving (both opening and closing), and then they will push on the end of the gate to simulate it striking an object. The operator should act as prescribed in the manual. If not, then the sensitivity setting of the operator may need to be adjusted.
Some gates may have “safety edges” attached to the ends of the gate (or the bottom, in the case of lift or barrier gates). These edges are “contact” safety devices, which require them to actually strike an object before detection happens.
To test them, they would be activated as the gate is opening or closing, depending on which end of the gate the device is attached. The operator should act as prescribed in its manual.
Emergency Opening Devices
Depending on your local fire codes, your gate may be required to have an emergency opening device attached. This could be a key switch inside of a fire department lockbox or a strobe light / siren activated sensor attached to the gate operator. This device should be tested regularly to make sure it is operating properly.
Cold Weather Situations
In areas with cold weather and ice, extra precautions should be taken.
- Some operators may be equipped with heaters for the gearbox or other items inside the operator. These may be controlled by a thermostat so that they only turn on below a set temperature. Check to make sure these devices are operating correctly before the onset of winter weather.
- Keep an eye out for any snow or ice buildup in the path of any electric eye type safety devices, and keep them clear.
- Keep the gate path clear of ice and snow buildup.
- Try to keep the gate itself from gathering ice. This is especially important for lift gates because extra weight may prevent the gate from opening. It may be a good idea to open the gate periodically when there is snow or ice, to help prevent a buildup. This process could be automated using your access control software or a programmable timer installed in the operator.