OMM-0153_E
• 5/11/2023 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page 7 of 124
CENTURION Installation, Operation & Maintenance Manual
0 FOREWORD
Technical Terminology Meanings
MBH
1000 BTUs per Hour
Modbus®
A serial, half-duplex data transmission protocol developed by AEG Modicon
NC (N.C.)
Normally Closed
NO (N.O.)
Normally Open
NOx
Nitrogen Oxide
NPT
National Pipe Thread
O
2
Oxygen
O.D.
Outside Diameter
OMM, O&M
Operation and Maintenance Manual
Predictive
Maintenance
An on-line remote monitoring system
PCB
Printed Circuit Board
PMC Board
Primary Micro-Controller (PMC) board, contained in the Edge
P/N
Part Number
POC
Proof of Closure
PPM
Parts per Million
PSI
Pounds per Square Inch (1 PSI = 6.89 kPa)
PTP
Point-to-Point (usually over RS232 networks)
P&T
Pressure and Temperature
ProtoNode
Hardware interface between BAS and a Water Heater
PVC
Poly Vinyl Chloride, a common synthetic plastic
PWM
Pulse Width Modulation
REF (Ref)
Reference
RES.
Resistive
RS232 (EIA-232)
A standard for serial, full-duplex (FDX) data transmission based on RS232 Standard
RS485 (EIA-485)
A standard for serial, half-duplex (HDX) based on the RS485 Standard
RTN (Rtn)
Return
SETPT (Setpt)
Setpoint Temperature
SHLD (Shld)
Shield
SPDT
Single Pole Double Throw, a type of switch
SSOV
Safety Shut-Off Valve
TAC
Turndown Adjustment Control
TEMP (Temp)
Temperature
Terminating
Resistor
A resistor placed at each end of a daisy-chain or multi-drop network in order to
prevent reflections that may cause invalid data in the communication
Tip-N-Tell
A device that indicates if a package was tipped during shipping
UL
A business that tests and validates products
VAC
Volts, Alternating Current
VDC
Volts, Direct Current
VFD
Variable Frequency Drive
VPS
Valve Proving System
W
Watt
WHM
Water Heater Management system
W.C.
Water Column, a unit of pressure (1 W.C. = 249 Pa)
µA
Micro amp (1 million
th
of an ampere)