NAC Power Supply

NAC Power Supply is the unavoidable part of the fire security system inside a building. It is therefore important to get the NAC Power Supply installed by professionals like NY Engineers who provide the best solutions to every security concern.

Customizable Supply

NY Engineers yearn to provide fully customizable NAC Power Supply systems that can be customized according to your need.

Reliable and Compatible

NY Engineers’ NAC power supply services are fully reliable and compatible. You can rest assured that the NAC Power Supply installed in your building or residence is fully functional.

Supervision and Maintenance

With NY Engineers, you don’t have to worry much about the NAC circuit supervision. We perform monthly maintenance checks on the NAC Power Supplies installed in your building. 

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NAC Power Supply

What is a NAC Power Supply?

NAC is an acronym which stands for “Notification Appliance Circuit”. So, there are essentially three parts to this particular product.

Notification: This means that the NAC Power Supply provides the notifications to the occupants. These notifications can be of fire or any other emergency which could prove to be fatal.

Appliance: The NAC Power Supply uses several different appliances to sound the notification and alert the occupants. These appliances include, but are not limited to horns, strobes, alarms, chimes, bells, klaxons and so on.

Circuit: A circuit simply means a closed loop of electrical devices and a power source. The circuit connects the power source of the building or residence to the notification appliances such as horns and strobes.

NAC Power Supply systems have been functioning in buildings and residences ever since the advent of safety standards in the industries. NAC Power Supply systems provide a sure-fire way to provide emergency notifications to the occupants of a particular building or residence.

The NAC circuit is designed to start at the main fire alarm panel and connects to the notification devices in the building or residence, thereby completing the circuit. The NAC circuit is usually a simple circuit which is designed by our expert engineers. This circuit is usually a two-wire circuit and makes use of an end-of-line resistor to end the circuit.

The NAC Power Supply system’s provided by NY Engineers works in two major modes: The Supervision mode and the Alarm mode. The Supervision or the Standby mode means that the NAC Power Supply will stabilize the power provided to all the appliances in the circuit without overworking the circuit or using too much power.

The Supervision mode is useful when you know you’re not doing critical work and there are lesser chances for an emergency situation. While the Alarm Mode is useful when you’re sure that there are more chances for there to be emergency situations such as a fire. The Alarm mode is usually used in places like mechanical rooms and testing rooms where the equipment is more likely to catch fire.

NY Engineers provide the NAC Power Supply with a simple switch which is basically a relay. This switch allows you to switch between the two modes for either convenience or for need. This is a physical switch that lies on the control panel of the NAC.

NAC Polarity

Polarity plays an important part in the NAC Power Supply system because it determines the modes and allows you to work between the two modes. With the NAC, the positive and negative polarity of the riser power is the complete and total opposite of the supervisory power. So this means that for any emergency purpose, the voltage on the NAC Power Supply System reverses itself. This only happens when the system goes into alarm mode via the physical relay switch on the control panel.

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Mounting Enclosures

The Notification Appliance Circuit should be properly mounted in an accessible area where the notifications can be sent out to the different appliances in the building or residence. This is extremely important for most regulatory standards where accessibility is a huge factor. NY engineers will make sure that all of the appliances and the NAC are properly installed in a place that is accessible to all the occupants.

We also make sure that any and all secondary battery box or some other accessory which is not connected through a protective measure or a circuit for remote connection should be within the same room and connected through an electrical conduit. It is important to remember that the installation procedure and the fitting procedure are very important and also very delicate. This is why we have our expert team of engineers does this for you, all the while taking important information about the building from you.

When mounting the enclosure on interior walls, our team uses appropriate screws in plaster. This is done after a thorough evaluation of the walls and the material used to build these walls. When mounting the enclosure on concrete, however, our engineers first attach a piece of plywood to the surface of the concrete. This is done especially when we expect that there will be imminent moisture.


Routing is a vital aspect of connecting the NAC to the actual appliances in the building. Routing is the process where the electrical signals and data cables are allowed to interact with the appliances and in turn produce notifications.

Routing is first planned out by our expert network engineers and electrical engineers. They will ask you for the blueprints to the building and then also ask for the circuitry for a particular room or floor. Once this is done, the routing will be designed on paper and presented to you for approval of the budget. After this, the wiring and the routing process begins which usually does not take a lot of time depending on your blueprint and the circuitry design.

All high voltage and the wiring which is not limited by power are kept separate from all wires that are limited in power. It is important that a 0.25-inch separation must be kept between the wires otherwise things can go haywire and the notification access panel can lose all control over the devices to which it is connected. It is also very important to maintain a separation of high voltage and wires that are not limited by power.

In order to avoid any induced noise or transfer or magnetic or electrical energy, our engineers try to keep the input wiring away from the high current producing and the limited power wires. Otherwise, an improper wiring plan and installation can cause the entire Notification Appliance Circuit to get out of orbit and stop working. It is therefore important to separate high current input and output wires from the low current and low voltage input and output wires.

Another important aspect is wiring within the cabinet of the Notification Access Circuit. The wiring within the cabinet must be properly routed and connected across the perimeter or boundary of the cabinet. It is imperative that these cables should not cross the PCB or the printed circuit board. This is because it could potentially induce noise or transfer unwanted electrical energy to the sensitive electronic parts. It could also pick up any sort of unwanted radio frequency signals or noise from the power supply circuit.

Wiring and Connections

NY Engineers offers NAC Power Supply systems with the modern connecting wires and sheaths. This is to make sure that even in the face of a fire, the alarms work just as they are supposed to. We also provide services to replace any sort of the previous wiring with new and improved wiring which is impervious to fire. This is optional and will add a preservation value for the electronics and electrical connections in the building.

But, our team of engineers will always make sure to put up wires and connections to the Notification Appliance Circuit and all other subsystems which it is connected to. These wires will be made to be fireproof and impervious to heat and any other kind of complication. So, you can rest assured that all of your safety systems will work regardless of the situation at hand.

Power Settings

Supplying power to the NAC system can be a problem because the power supply for the entire building may be the cause of the fire. This is why we highly recommend our clients to have the Notification Appliance Circuit either attached to the emergency generator systems. Or in other cases, we suggest connecting them to dedicated generator systems which will help them run.

NY Engineers also provide generators to clients. We can arrange to have a generator installed for your building or residence so that it can effectively power up the Notification Appliance Circuit. This Notification Appliance Circuit will then be connected to the emergency generator which will be put on standby mode.

We also recommend getting batteries installed in the building and then connected to the Notification Appliance Circuit. This is because sometimes the emergency generator systems also get burned or corrupted and fail to start up the whole system. For this purpose, it is better to have a large battery or collection of batteries installed and connected.

NY Engineers provide batteries from a third-party source; however, we also make sure that these batteries are fully tested by our team of skilled engineers. These batteries are tested and made to be fully functional and kick in once the emergency generators fail. The battery is stored in another room where it is kept in special conditions in order to make sure that the batteries do not get all ruined.

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Supervising the NAC

In addition to installing the Notification Appliance Circuit, it is also important to properly and actively supervise the system as well. This supervision circuit is very similar to the IDC (the Initiating Device circuit) but it is not exactly like it. Unlike the IDC, this supervision circuit cannot be used to power up any kind of device.

The supervision for the NAC system has three factors or conditions:

Normal: This condition means that the voltage measured at the panel of the NAC is lower than the alarm level voltage but it should be greater than shorted wire voltages. The supervision current should also not go through any of the devices or appliances.
Trouble open: This means that the voltage of the NAC measured at the panel is higher than the normal supervision voltage. This indicates that somewhere in the circuit, wire or connection has broken.
Trouble short: This condition means that the voltage measured at the NAC is lower than the normal supervision voltage. This could be because of a short circuit.

Maintenance and Testing

In order to make sure that all of your NAC Power Supply is working and up to the standard, our team of highly skilled engineers visits the building every 6 months. This maintenance is important because your NAC Power Supply system may develop faults or errors over time which can be a huge problem for you to deal with. This is also dangerous when you are faced with a real emergency and your NAC system then malfunctions or succumbs to a few wiring or electrical faults.

Our maintenance teams check each and every aspect of the NAC Power Supply. This includes the subsystem installed in it as well as the wiring, the power sources and the integration. This is done through rigorous testing methods and procedures which our engineers perform. This may take a full week or even two weeks to fully test out. This depends on the kind of building and the kind of NAC system that you got installed.

As an alternative, our team of engineers and experts can also train your employees to perform the maintenance and testing procedures themselves, however, this is a lengthy process and costs more. This is also not as efficient as having our own engineers and experts to carry out.

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