ONICON Incorporated 727-447-6140
Page 5
www.onicon.com
SYSTEM-20 BTU METER
SECTION 1.0
INTRODUCTION
The purpose of this guide is to provide installation and commissioning procedures, and
basic operating and servicing instructions for the ONICON SYSTEM-20 BTU Meter.
WARNING (4)
Only qualified service personnel should attempt to install or service this product.
Serious injury may result from the improper installation or use of this product.
ONICON’s System-20 is a true heat (Btu) computer, which accepts data from several
sensors, performs a series of computations with that data, and displays and/or transmits
the results as an indication of the amount of heat (Btus) being transferred per unit time or
as a totalized amount.
1.1 PURPOSE OF THIS GUIDE
1.2 TYPICAL SYSTEM-20
BTU METER
SUPPLY
RETURN
HEAT
EXCHANGER
BTU METER
SYSTEM-20
Made in USA
BTU/HR
49.50
1
3
FLOW
4
5
6
2
1. Class II Inpu Power 20-28 AC/DC, 50/60 Hz
2. Input and Output Signals - Three (3) pulse iinputs,
three (3) pulse outputs, one (1) analog output
3. RS485 BACnet or MODBUS
4.
ONICON Water Flow Meter (ordered separately)
5. Return Temperature Sensor
6. Supply Temperature Sensor
1.3 STANDARD FEATURES
AND SPECIFICATIONS
• Single mode Btu calculations, in either the heating or cooling mode, are
totalized, and displayed.
• Two-pipe dual mode Btu calculations in both the heating mode and the
cooling modes, are totalized and displayed.
• A single isolated RS485 serial interface is provided for BACnet
®
MS/TP or
MODBUS
®
RTU.
•
Three field configurable pulse outputs may be used for totalization, alarm
indication and mode status.
• Three auxiliary pulse inputs may be used to totalize data from external
devices. This data may also be transmitted via the network interface and
viewed on the local display.
•
A single field configurable isolated analog output is provided for energy
rate, flow rate or temperature.