The Form 16s meter is one of the most commonly used meter forms to meter a three phase service. It is what is known as a self-contained meter, meaning that all of its parts are contained under the cover.
What type of service does a Form 16s meter?
The Form 16s meter is typically used to meter the 4 wire wye service. This service generally comes in two different voltage choices. It is normally available as a 120/208v service, or a 277/480v service.
Also, this meter is normally only used on services of less than 400 amps. A CL 320 Form 16s meter is used for 400 amp services, while a CL 200 Form 16s meter is used for 200 amp services and less.
What kind of meter base does a Form 16s meter use?
This meter utilizes a seven terminal meter base. It is also very common to find seven terminal meter bases that have meter bypass capabilities. In this type of meter base there is generally a handle that must be raised in order to bypass the meter.
Some meter bases that utilize bypass handles actually open the jaws of the meter base allowing for easy installation and removal of the meter. One thing that you must remember when dealing with a meter base that has bypass capabilities is that both the top and bottom side (line and load side) of the meter base remain energized when the bypass handle is in the closed position.
Best Practices
Although Form 16s meters can be used in 277/480v services, my opinion is that this should be avoided whenever possible. The reason for this is that whenever the meter is installed and removed, there is a great potential for an arc flash. The better option for 277/480v services is to install a CT Cabinet and use PTs to step the voltage down to a safer level.