The Generator Tap Box: Uses & Costs

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Most of the power that’s used in a good number of households is actually provided by a utility company that’s generally connected to the onsite application. However, when this power ceases to work, a new or used generator can importantly be a very good tool to provide power. Additionally, a generator can automatically or manually be connected to an onsite application through a transfer switch. The primary job performed by a transfer switch is to transfer power from the grid to an alternative source of power. On that note, in the following discussion, we are going to look at how the control panel manages an automatic transfer switch.

Moreover, the transfer switch generally has a control panel that makes the entire system automatic by nature. There are normally two types of transfer switches, the manual transfer switch, and the automatic transfer switch. The manual transfer switch is normally operated by onsite personnel, and it’s usually very important in circumstances where the load is not of emergency or requiring instant restoration of the power supply. With the automatic transfer switch, power failure is immediately detected, and the adjustment from the utility power to the generator power is seamless.

The control panel’s major task is to detect the power failure and immediately start the generator’s engine. Immediately the generator reaches the correct frequency and voltage; the control system notifies the switch to shift the normal transmission of power to the generator. It’s actually quite complex trying to understand the automatic transfer switch since there are the time delay and other components that play a significant pivotal role in ensuring the entire unit works correctly.

Frequency and voltage sensing

Detection of a complete failure of the power source and drop of voltage is actually one of the primary function of the control panel. There are usually many phases involved, and each phase is monitored. A drop in voltage in any phase is regarded as a failure at that point. The control panel contains a sensor that provides the frequency and voltage information which is basically used to establish load availability. Before a transition from the load to the generator purchased from takes place, a minimal frequency and voltage must first be attained. This is very important because it ensures that the generator is in a position that it can accept the load.

Time Delays

In normal circumstances, automatic transfer switches come with a time transfer feature which is very significant because of the false alarm triggers the normal source of power from a utility company. What basically happens is that the most widespread time delay overrides other short-lived normal outages preventing any erroneous engine start hence load transfer. The time delay is usually between 0 and 6 seconds with one second being the common setting.

Furthermore, after the restoration of the power, another time delay is actually required to ensure the load can take back the power from the generator. However, this delay is unique, and it’s normally between 0 and 30 minutes. If the generator fails and the normal source of power is ok, the control panel ought to automatically bypass this time delay.

The other time delay involved is one during the engine cool down period. At this moment all the controls run the engine unloaded before they temporarily shut it down. Time delays are very significant elements when it comes to the transfer of the load from the normal source of power to a backup generator and vice versa.

Engine control Contact point

When talking about an engine control contact point, it basically refers to the engine controls that signals the engine controls to start up when the normal power supply from the grid goes off. What primarily happens about the modern designs is that there is a dry contact which closes up the gap when the normal power fails.

When this happens, a complete circuit is created from the cranking batteries to the backup engine start control system. When the power from the grid is back, the contact point opens resulting in the shutting down of the backup generator. It’s always a recommendation to carry out regular checkup to the contact point so that a problem cannot be incurred in completing the circuit.

Control system testing

This is actually part of emergency power system maintenance. It’s normally done periodically, and it’s always important that all control system possesses a manually operated switch for purposes of simulating the normal power failure. All the features described in this discussion are about an automatic transfer switch, and they should actually be a minimum consideration for anyone who wants to purchase a transfer switch.

Nevertheless, there are many controls that are required for the operation of different applications. Before you settle on one, always consult an electrical contractor to establish the controls which best suits your particular needs.