TIME STAMP: THIS IS A CONTROLLED DOCUMENT AS LONG AS NO NEW RELEASED REVISION SUPERSEDES IT.
PRINTED ON THIS DATE: 8/23/2021 AND TIME: 10:19:40 AM.
Introduction, Power Requirements, and Signal Interface
Introduction
Your Valumass™ flow meter includes a flow sensing element, temperature sensing element,
digital SIM/Base board, digital controller board and a transmitter enclosure. The flow sensor is
mounted in an insertion probe support or an inline flow section. Depending upon your
requirements, all these components may be integrated into one flow transmitter assembly or
you may have a flow transmitter and a second, remote electronics enclosure. In either
configuration, the digital controller converts the nonlinear input signal received from the flow
sensor to linear 0–5/10 VDC & 4–20 mA output signals. RS485 Modbus RTU communications
are embedded in the firmware as standard, with optional BACnet communications available.
Unpacking Your Instrument
Although your Valumass™ thermal mass flow meter instruments are rugged, they should be
inspected upon delivery to assure that no damage has taken place during transit. If upon
inspection it is found that damage has occurred, notify the carrier immediately and place a claim
for damaged goods. The shipping container or crate should be handled with care and carefully
opened to avoid possible damage to the contents. After the container is opened the contents
should be carefully removed and the individual pieces checked against the packing list. Please
note that the packing list will show all the options that were ordered for your instrument. Most of
these options will be incorporated into the flow meter itself and will not be separate components.
The last verification is to check that the equipment and calibration range as shown on the
documentation match your purchase order specifications. If you discover a discrepancy or have
any questions about what you have received, contact EPI immediately.
Power Requirements
Power requirements for Valumass™ flow meters with the “-DC24” option is user-supplied 18 to
24 Volts DC @ 250 mA.
Power requirements for Valumass™ flow meters with the “-AC115” option is 100 - 120 VAC
50/60 Hz standard.
Power requirements for Valumass™ flow meters with the “-AC230” option is 210 - 240 VAC
50/60 Hz Standard.
Our recommendation on wire size is 18 Ga. stranded for all AC wiring. If conduit is used to
enclose the power input line, it should be suitable for the application, electrically conductive, and
connected within the enclosure to the earth ground. If the flow meter includes a remote
electronics assembly, then the flow transmitter power is provided by the connection to the
remote assembly. Ten feet of five-wire connection cable is provided with the standard remote
assembly. If more cable is required, please inform your EPI sales representative at the time of
order. The transmitter is independent of cable length and will not suffer any signal degradation
with length changes. The 4–20mA analog output wire should be sized for no more than 5 Ohms
resistance across the loop and not less than 22 AWG.
