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FORM 160.54-M1
ISSUE DATE: 10/25/2019
PWM
The Pulse Width Modulation input is in the form of a
1 to 11 second relay contact closure that applies 115
VAC to the I/O Board TB4-20 for 1 to 11 seconds. As
shown in Figure 34 on page 102, connect dry closure
relay contacts between I/O Board TB4-20 (signal) and
TB4-l (115 VAC). The setpoint varies linearly from
100% to 30% as the relay contact closure time changes
from 1 to 11 seconds. The relay contacts should close
for 1 to 11 seconds at least once every 30 minutes to
maintain the setpoint to the desired value. If a 1 to 11
second closure is not received within 30 minutes of the
last closure, the setpoint is defaulted to 100%. A clo-
sure is only accepted at rates not to exceed once every
70 seconds. This input will only be accepted in Digital
Remote Mode. Calculate the setpoint for various pulse
widths as follows:
Setpoint (%) = 100 – [(pulse width in seconds – 1) x 7]
For example, if the relay contacts close for 3 seconds,
the setpoint would be set to 86% as follows:
Setpoint (%)
= 100 – [(3 –1) x 7]
= 100 – (2 x 7)
= 100 – 14
= 86%
RS-232
As shown in Figure 29 on page 93, a setpoint can
be received in serial data form at Microboard J2 from
the E-Link.
LEAVING CHILLED LIQUID TEMPERATURE
Remote Leaving Chilled Liquid Temperature setpoint
with 0 to 10 VDC, 2 to 10 VDC, 0 to 20mA, 4 to 20mA
or Pulse Width Modulation Signal – Remote Leaving
Chilled Liquid Temperature setpoint reset can be ac-
complished by supplying (by others) a 0 to 10 VDC,
2 to 10 VDC, 0 to 20mA, 4 to 20mA or 1 to 11 second
Pulse Width Modulated (PWM) signal to the OptiView
Control Center. The Leaving Chilled Liquid Tempera-
ture setpoint is programmable over any of the follow-
ing ranges:
• 38°F to 70°F (water applications)
• 36°F to 70°F (water applications with Smart
Freeze protection enabled)
• 10°F to 70°F (brine applications)
JOHNSON CONTROLS
The Remote Input Signal changes the setpoint by cre-
ating an offset above the locally programmed Leaving
Chilled Liquid Temperature Base setpoint value. The
setpoint can be remotely changed over the range of the
value programmed for the Remote Reset Temperature
Range setpoint (10, 20, 30, or 40°F with Software ver-
sion C.OPT.01.18.307 (or later); 10 or 20°F with ear-
lier software versions).
For example, if the Local setpoint is 40°F and the Remote
Reset Temperature Range setpoint is programmed for
10°F, the Leaving Chilled Liquid Temperature setpoint
can be remotely reset over the range of 40°F to 50°F.
The setpoint received through the COM 4B RS-232 se-
rial port is not an offset that is applied to the locally pro-
grammed "base" value as described above. Rather, it is
an actual setpoint value. The locally programmed value
is not used as a "base" in this application.
The OptiView Control Center must be configured ap-
propriately to accept the desired signal type as follows:
• The appropriate Remote Mode must be selected:
a. Analog Remote Mode must be selected when
using a voltage or current signal input.
b. Digital Remote Mode must be selected when
using a PWM input.
• If Analog Remote Mode is selected, the Remote
Analog Input Range setpoint must be set to 0 to
10 VDC or 2 to 10 VDC as detailed below, regard-
less of whether the signal is a voltage or current
signal type.
• Microboard Program Jumper JP24 must be posi-
tioned appropriately per the input signal type as
detailed below. It is recommended a qualified Ser-
vice technician position this jumper.
JCI COMPANY CONFIDENTIAL
SECTION 22 - REMOTE SETPOINTS
IMPORTANT! - The signal type used for
Remote Leaving Chilled Liquid Tempera-
ture setpoint reset and the signal type used
for Remote Current Limit setpoint reset
must be the same. For example, if a 0 to
10 VDC signal is being used for Remote
Current Limit setpoint reset, then a 0 to
10 VDC signal must be used for Leaving
Chilled Liquid Temperature reset.
22
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