10
Output Function
Switches
How to Configure Output Function Switches
There is a switch assembly on the bottom board (see bottom
board illustration). This four-position switch regulates cycle
time and output selection. It is factory-configured for the plug-
in output ordered. Check the output function chart to make
sure the configuration is correct for your application. Figure 5.
Switches 1&2: These switches act together to select either
proportional current output or one of the time
proportioning cycle times. (See the output
function switch chart.) Use longest times to
get best relay life expectancy. If meter shows
temperature swings following each “on” cycle,
select a faster time to reduce “ripple.”
Switch 3: Selects either on/off or proportional action.
“On” provides proportional action. “Off” pro-
vides on/off action.
Switch 4: Selects output for either mechanical or solid
state relays.
On: Provides slow proportional times for
mechanical relays
Off: Provides 20 mAdc when used with the “F”
module or fast time proportioning times
when used with “S” or “T” modules.
NOTE: Switch 4 changes the cycle times in conjunction with
switches 1 and 2. Check output function switch chart.
NOTE:
Reconfigured or
field-modified units
should always be
checked to assure
that output switch
positions are cor-
rect.
Proportional Band Adjustments for All Outputs
The proportional band adjustment widens or narrows the
band over which proportional action occurs. Too narrow a
band can cause the temperature to swing about the setpoint.
This can be seen on the deviation meter. Too wide a band
can cause an error between the setpoint and the actual tem-
perature (droop error) as measured at the sensor.
Proper setting of this adjustment is the point where the tem-
perature swings just stop. When adjusting the proportional
band control, do so in small increments, allowing time
between each adjustment for the process to stabilize.
Turning the adjustment in a clockwise direction widens the
proportional band and should reduce swings to straight line
control with most processes.
Offset (Manual Reset)
After the proportional band is set, the process temperature
may stabilize at a point other than the setpoint, high or low, as
shown on the deviation meter. This can be corrected with the
offset (manual reset) adjustment. If the deviation meter indi-
cates a low temperature, turn the offset (manual reset) adjust-
ment clockwise (+ direction) until the deviation meteris at
zero. Turn the offset (manual reset) adjustment counter-clock-
Adjustments
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