From PTI Security Systems
Power fluctuations and surges are issues that are faced by all access control systems and electronics. The controller has excellent built-in surge protection; however, if you are in an area that is prone to brownouts, blackouts, electrical storms, or other major power interruptions or fluctuations, we recommend that your system be equipped with the following safeguards against these problems.
- Obtain adequate lightning insurance coverage from an insurance agent for all electronic equipment if you are in an area that is prone to regular lightning strikes or electrical storms.
- UL rated power supplies adequately rated to provide at least 12 volts (AC or DC) and no more than 18 volts (AC or DC) at each AI device as well as providing sufficient amperage throughout the system.
- Power conditioning and surge suppression in the form of an uninterruptible power supply (UPSProvides power surge protection, power conditioning, and battery backup. Recommended for all computers, including Site Graphics (if present).) system connecting the controller, the access control system’s power supplies, and any computers to the 120V power. The controller and system power supplies must be connected to separate UPSs from the computer. Each component plugged into a UPSProvides power surge protection, power conditioning, and battery backup. Recommended for all computers, including Site Graphics (if present). reduces the actual battery backup time.
- Ditek or Opto-Isolator surge protection for the RS232A type of communications used for computers and serial devices. Generally, limited to fifty feet of wire length. One of the options used for connecting the Falcon XT to the StorLogix computer, but should be used only when the other options are not available. and RS485A type of communications used for electronic devices. Generally, limited to four thousand total feet of wire length. Used for connecting the Falcon XT to AI Devices. at the controller and at each AI device.
- Gates, door strikes, and elevators should have battery backup or other safety measures that meet local and national electrical codes.
- Office computers, copiers, fax machines, telephones, and other electronics should be plugged into surge protectors or a separate UPSProvides power surge protection, power conditioning, and battery backup. Recommended for all computers, including Site Graphics (if present)..
- For ongoing power issues, contact your local electrical company for their recommendations. Often, they can install power conditioners and/or surge suppressors on the incoming power lines to help protect your site.
Surge suppression equipment will not work adequately if the site does not have a good Earth Ground. If you are having a problem with surges and equipment damage at a site, the first step is to verify that the Earth Ground is within specifications (25 ohms or less). Earth grounds can change over time for various reasons, so you cannot rely on a test that may have been done when the site was first installed some time before.
There are several types of power risks to be aware of and protect against:
- Brownouts or power sag is when the power at the wall outlet drops below 115VAC (in the United States). This can be due to the utility company reducing power due to load issues or it can occur when large appliances cycle on in an overloaded circuit.
- Dirty Power occurs in some municipalities with antiquated or overloaded power grids. This is where the wall outlet power has consistent occurrences of small power spikes and brownouts. This is very damaging to electronics.
- Blackouts occur when power is completely lost at the wall outlet. This can happen due to storms, damage to power poles and lines, or to power grid problems. Blackouts are often followed immediately by power surges or brownouts when the power comes back on and large appliances cycle on.
- Surges are large spikes of power over 120VAC (in the United States). These can happen due to electrical storms, lightning strikes, and power grid problems. These can damage and sometimes destroy electronics.
- Lightning can cause problems in multiple ways. Indirect strikes that do not actually hit the system can cause static discharge, disrupting electronics. Direct strikes can travel along any conductive metal, cable, or other material damaging everything in its path. Lightning is harder to deal with as it could come in on the power, data, or relay connections or even through the conduit, building walls, or equipment cases.
Below is an example of how surge suppression components can be added to a system.
- ↑ These recommendations should provide protection against most common power surges, power fluctuations, indirect lightning strikes, and general electrical storm activity; unfortunately, due to the naturally destructive nature of lightning and electrical storms, there is only so much protection that can be provided to any hard-wired electronic system. Any local or direct strike may damage one or more pieces of electronic equipment in the vicinity and may damage or destroy the surge protectors or even, in some cases, the entire system. Considering that lightning is powerful enough to arc more than 12 miles across the sky, there is not much that you can do to protect any electrical equipment against a direct strike other than to have appropriate lightning insurance.
- ↑ Uninterruptible Power Supplies are the best option in the consumer market for protecting most electronics. A UPSProvides power surge protection, power conditioning, and battery backup. Recommended for all computers, including Site Graphics (if present). does three things: 1: Conditions incoming power to help prevent minor power spikes and temporary power drops (brownouts) from damaging the electronics. 2: Protects against major power surges with better protection than most surge protectors. 3: Provides temporary battery backup in case of complete power loss. The duration of backup time varies by the type of UPSProvides power surge protection, power conditioning, and battery backup. Recommended for all computers, including Site Graphics (if present). and the items that are plugged into it. Most UPSs offer an insured guarantee should an electronics product be damaged by a surge. You can purchase a UPSProvides power surge protection, power conditioning, and battery backup. Recommended for all computers, including Site Graphics (if present). from PTI Security Systems or at almost any computer or office supply store.
- ↑ Do not confuse a ‘power strip’ with a ‘surge protector’. Often, surge protectors are located right next to power strips in the store and look very similar. Power strips merely add additional outlets while surge protectors actually provide electrical protection. Look for the words ‘surge protection’ on the packaging and purchase a well known brand. Many high-end surge protectors offer insurance against damage to electronics if the surge protector fails to protect them. Buying the better model surge protector doesn’t cost much more and will provide peace of mind that your electronics are protected.