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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%
REMOTE LEAVING CHILLED LIQUID SETPOINT
with 0-10VDC, 2-10VDC, 0-20mA, 4-20 mA or
Pulse Width Modulation Signal
Remote Leaving Chilled Liquid Temperature Setpoint
Reset can be accomplished by supplying (by others)
a 0-10VDC, 2-10VDC, 0-20mA, 4-20 mA or 1 to 11
second Pulse Width Modulated (PWM) signal to the
Control Center. The Leaving Chilled Liquid Tempera-
ture Setpoint is programmable over the range of 38°F
to 70°F (water applications), 36°F to 70°F (water ap-
plications with Smart Freeze Protection enabled) or
10°F to 70°F (brine applications).
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
10° or 20ºF (as per the locally programmed Remote
Reset Temperature Range setpoint) above the Local
Leaving Chilled Liquid Temperature Setpoint. For ex-
ample, 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 Control Center must be confi gured ap-
propriately to accept the desired signal type as fol-
lows:
• The appropriate Remote Mode must be selected:
Analog Remote Mode must be selected when using
a voltage or current signal input. 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-
10VDC" or "2-10VDC" as detailed below, regard-
less of whether the signal is a voltage or current
signal type.
• Microboard Program Jumper JP24 must be po-
sitioned appropriately per the input signal type
as detailed below. It is recommended a qualifi ed
Service Technician position this jumper.
JOHNSON CONTROLS
SIGNAL
+
COMMON
FIG. 12 – REMOTE LEAVING CHILLED LIQUID TEMP.
SETPOINT WITH 0-10VDC OR 2-10VDC
SIGNAL
As shown in FIG. 12, connect input to
0-10VDC -
Microboard J22-3 (signal) and J22-5 (gnd). A 0VDC
signal produces a 0
F offset. A 10VDC signal provides
°
the maximum offset )10
setpoint value). The setpoint is changed linearly be-
tween these extremes as the input varies linearly over
the range of 0VDC to 10VDC. This input will only be
accepted when "Analog" Remote Mode is selected,
the "Remote Analog Input Range" setpoint is set for
0 - 10 Volts, and Microboard Program Jumper JP24
has been removed. Calculate the setpoint for various
inputs as follows:
OFFSET
°F) = (VDC)(REMOTE RESET TEMP. RANGE)
(
SETPOINT (
F) = LOCAL SETPOINT + OFFSET
°
For example, if the input is 5VDC and the remote Reset
Temperature Range setpoint is programmed for 10
the Local Leaving Chilled Liquid Temperature setpoint is
programmed for 40
F, the setpoint would be set to 45
°
follows:
OFFSET (
= 50
= 5
SETPOINT (
= 45
2-10VDC - As shown in FIG. 12, connect input to Microboard
J22-3 (signal) and J2-5 (gnd). A 2VDC signal produces a
0
°
F offset. A 10 VDC signal produces the maximum allowed
offset (10
F or 20
F above the Local Setpoint Value). The
°
°
setpoint is change linearly between these extremes as the
input varies over the range of 2VDC to 10VDC. This input
will only be accepted when "Analog" Remote Mode is
FORM 160.67-PW2 (1007)
J22
3
5
LD04500
F or 20
F above the local
°
°
10
°
F and
F as
°
°
F) = 5 x 10
10
10
F
°
F) = 40 + 5
°
F
°
9
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