Technical Bulletin—TC-9100 Universal Controller
17
The 2-stage on/off output type may be configured in pairs of output
modules – OCN1/OCN2, OCN3/OCN4, and OCN5/OCN6.
The output is a pair of digital outputs (triacs) that are switched on in
sequence as the controller output increases. The first stage digital output
is switched as soon as the output is above 0% and the second stage digital
output is switched when the output is equal to the set load rating for the
first stage, which is set as a configuration parameter along with the
switching differential.
Note: To ensure that the first stage switches off, the low limit of the
control module to which the 2-stage output module is connected
must be set at the switching differential value as a negative
number. For example, if the differential is set at 5%, then the low
limit of the control module must be set at -5%.
Two-stage output modules may be connected to programmable modules
configured as Algorithm 2, 4, or 6, or as calculation algorithms 7 to 12,
provided that the output range covers the switching differential, as
explained above.
}
Differential
}
Differential
Stages 1 and 2
Stage 1
Off
0
100
Module
Output
Process Variable
Load Rating
of Stage 1
Figure 5: 2-Stage On/Off Output
An on/off output type may be configured for output modules OCN1 to
OCN6. The output is a single triac that is switched on when its source
signal is greater than 0, and switched off when the source signal is equal
to or less than 0. The on/off output module is normally connected to a
programmable module configured as Algorithm 1, 3, or 5 (an on/off
controller), and the switching differential is provided by the on/off
controller.
2-Stage On/Off
On/Off Output
Type