12-1 Copyright  2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e Chapter 12 METERS

12-2 Copyright  2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e Function of a meter The function of a gas meter is to measure the volume of gas used. Location of the meter and the type of meter connections to be used are normally determined by the local authority.

General meter information The badge plate of the meter gives the following information: Capacity in cubic metres (m³). Cyclic capacity or capacity per revolution. Name of the manufacturer. Meter number. Year of manufacture. Repair date (when applicable) Copyright  2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Types of meters Positive displacement - Wet positive displacement meters. - Dry positive displacement meters. Rotary or flow Ideal for measuring large gas rates Copyright  2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Installation meters Location of the gas meter is determined by the local authority, but generally it needs to be located where it is easily accessible and not subject to damage or exposed to detrimental conditions. Domestic premises—the meter is usually located at the front of the property. Local authority rules and AS 5601 apply to the installation of meters and associated equipment Copyright  2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Types of meter installations Master meter This meter is connected to the inlet service and supplies gas to subsidiary meters. Subsidiary meter This meter is not connected to the service but it meters gas which has previously passed through a master meter Copyright  2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Subsidiary meter installation 12-7 Copyright  2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Bonding straps Electrical leakage may take place because of faulty electrical equipment. Bonding straps must be fitted to inlet riser and outlet riser (metallic pipes) Copyright  2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Reading gas meters Metric meters show the index by using digits. –The first four numbers from left are used to record gas consumed. – Last three digits can be used when checking gas rates Copyright  2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Checking gas rates The test dial on a gas meter is used to check gas rates of appliances or to check the rate of gas escapes. Formula: GR= HV X V X H T GR = Gas rate in m³ HV = Heating value of gas in MJ/m³ V = volume of gas measured H = number of seconds in 1 hour T = number of seconds to conduct tests Copyright  2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Meters—Summary Function of a meter is to measure the volume of gas used. Types of meters –Positive displacement –Rotary or flow Installation of meters to be to local authority requirements. Bonding straps to be used when disconnecting meters Copyright  2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e