Det-Tronics R8471NH34001,2,3 Single Channel Gas Controller, NH3 - Manual (Page 7)

5 95-8529 1.1
Setpoints
The controller has three independent alarm outputs
(low, high and auxiliary), with field selectable
setpoints.
The programmed calibration gas time is displayed
and adjusted along with the alarm setpoints.
The alarm setpoints and calibration gas time can be
checked and/or changed using pushbuttons located
on the front panel of the controller.
The alarm setpoint and calibration time adjustment
ranges for the R8471D (Cl
2
) controller are:
Low alarm: 0.5 to 5 ppm
High alarm: 1 to 9 ppm
Auxiliary alarm: 0.5 to 9 ppm
Calibration time: 16 seconds to 8 minutes
The alarm setpoint and calibration time adjustment
ranges for the R8471F (SO
2
) controller are:
Low alarm: 5 to 50 ppm
High alarm: 10 to 90 ppm
Auxiliary alarm: 5 to 90 ppm
Calibration time: 16 seconds to 8 minutes
The alarm setpoint and calibration time adjustment
ranges for the R8471G (NO
2
) controller are:
Low alarm: 1 to 10 ppm
High alarm: 2 to 18 ppm
Auxiliary alarm: 1 to 18 ppm
Calibration time: 16 seconds to 8 minutes
See “Setpoint Adjustment” section of this manual for
complete information.
Outputs
The controller is available in a Base version and a
Premium version. The differences between the two
models are the output configuration and programming
options.
Base Model - The base controller is furnished
with open collector transistor outputs (rated 100
milliamperes at 32 volts dc) for the Low alarm,
High alarm, Auxiliary alarm, and Fault circuits. The
normally “off” alarm outputs are turned “on” (transistor
conducts, collector is pulled to ground) when their
corresponding setpoints are reached. The fault
output is normally on and turns off upon detection of
a system fault.
The low alarm, auxiliary alarm, and fault outputs are
non-latching. The high alarm output is latching.
Premium Model - The premium model is furnished
with a set of four relays in place of the four solid state
outputs. The relays have SPST contacts rated 5
amperes at 30 vdc/250 vac.
This model also includes a selectable isolated/non-
isolated 4 to 20 ma current output for transmitting
system information to other devices. The linear 4
to 20 ma output corresponds to gas levels from 0
to 100% full scale. If a system fault is detected, the
output drops to less than 1.0 ma. The current output
can be calibrated in the field to ensure maximum
accuracy. (Refer to the “Calibration” section of this
manual for details.)
Programming Options (Premium model only) -
Each of the four relays is field selectable for either
normally open or normally closed contacts using
jumper plugs located on the printed circuit board
inside the controller. (See Table 5.)
The alarm relays are also switch programmable for
either normally energized or normally de-energized
operation (programmable as a group only, not
individually). The fault relay is normally energized.
The low and auxiliary alarm relays are switch
programmable for either latching or non-latching
operation. The high alarm relay is always latching and
the Fault relay is non-latching. Latching relays are
reset using either the RESET pushbutton on the front
panel of the controller or an external reset switch.
The 4 to 20 ma circuit is selectable for isolated or non-
isolated operation.
Table 5—Selectable Relay Options
Relay Selectable Selectable Selectable
Normally Normally Latch/
Open/Closed Energized/ Non-Latch
De-Energized
Low Y Y
1
Y
1
High Y Y
1
N
2
Auxiliary Y Y
1
Y
1
Fault Y N
3
N
4
Y = Yes N = No
1Selectable as a group, not individually 2Latching only
3Normally energized only 4No latching option