A.O. Smith 100 Series, Руководство по обслуживанию

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Servicing should only be performed by a Qualified Service Agent
COMMUNICATIONS AND DISPLAYS
Two modes of communications are available to the R7910.
1. The R7910 has two RS485 communication ports for ModBus that allows for interfacing to one or all R7910s of a system
and presents them individually to the user. The S7999D System Operator interface is a color touchscreen display used for
configuration and monitoring of the R7910A. Though configuration can be done through the display, it is not recommended as
all the parameters are pre-configured by the manufacturer. Any custom configuration required by the field should be done in
consultation with the A. O. Smith qualified service technician. Control Operation and display status in both test and graphical
modes can be shown along with the ability to setup. The R7910 can also be remotely reset through the S7999D display.
2. Either ModBus RS485 communication port can be used to allow configuration and status data to be read and written to the
R7910. Support a Master S7999D or a Building Automation master to control the R7910 to respond to a single ModBus address
to service the requests of the ModBus master in a Lead/Lag arrangement.
SPECIFICATIONS
1. Electrical Ratings:
Operating voltage
• 24VAC (20 to 30 VAC, 60 Hz ±5%)
• 30 amps (Single Heat Exchanger)
• 60 amps (Double Heat Exchanger)
Connected Load for Valve and annunciator functions:
• 24VAC, 60Hz
• 120VAC (+10%/-15%), 60Hz (±5%)
• Model Specific
2. Corrosion:
• R7910A must not be used in a corrosive environment.
3. Operating Temperature: -4°F to 150°F (-20°C to 66°C)
4. Storage/Shipping Temperature: -40°F to 150°F (-40°C to 66°C).
5. Humidity:
• Up to 95% Relative Humidity, noncondensing at 104°F for 14 days. Condensing moisture may cause safety shutdown.
6. Vibration: 0.0 to 0.5g Continuous (V2 level)
7. Enclosure: Nema 1/IP40.
8. Approvals:
Underwriters Laboratories, Inc. (UL): Component Recognized: File No. MP268 (MCCZ)
• R7910 is certified as UL372 Primary Safety Controls.
• The R7910 is certified as UL353 Limit Rated device when using part number 50001464 dual element limit rated NTC sensors.
CSD-1 Acceptable.
Meets CSD-1 section CF-300 requirements as a Primary Safety Control.
Meets CSD-1 section CW-400 requirements as a Temperature Operation control.
Meets CSD-1 section CW-400 requirements as a Temperature High Limit Control when configured for use with 10 kohm NTC sensors.
Federal Communications Commission, Part 15,
Class B. Emissionss.