York YLAA0170 Installation Operation & Maintenance

JOHNSON CONTROLS
159
SECTION 8 – UNIT OPERATION
FORM 150.72-ICOM6
ISSUE DATE: 12/29/2017
8
REMOTE BAS/EMS TEMPERATURE RESET
USING A VOLTAGE OR CURRENT SIGNAL
The Remote Reset Option allows the Control Center
of the unit to reset the chilled liquid setpoint using a
0 to 10VDC input, or a 4 to 20mA input connected
to XTBC1 Terminals A- and A+. Whenever a reset is
called for, the change may be noted by pressing the
COOLING SETPOINTS key twice. The new value
will be displayed as “REM SETP = XXX °F.”
If a 0 to 10VDC signal is supplied, it is applied to Ter-
minals A+ and A-, and jumper JP1 on the I/O board
must be inserted between pins 2 and 3. To calculate the
reset chilled liquid setpoint for values between 0VDC
and 10VDC use the following formula:
Setpoint = Local Chilled Liquid Setpoint + °Reset
°Reset = (DC voltage signal) x (*Max Reset Value)
10
Example:
Local Chilled Liquid Setpoint = 45 °F (7.22 °C)
*Max Reset Value = 20 °F (11.11 °C)
Input Signal = 6VDC
(English)
°Reset = 6VDC x 20 °F
10
New Setpoint = 45 °F + 12 °F = 57 °F
(Metric)
°Reset = 6VDC x 11. 11 °C
10
New Setpoint = 7.22 °C + 6.67 °C = 13.89 °C
* Max Reset Value is the “Max EMS-PWM Remote Temp. Reset”
setpoint value described in Remote Setpoint Control on page
125 under “Cooling Setpoints”. Programmable values are from 2
°F to 40 °F (1.11 °C to 11.11 °C).
= 12 °F Reset
= 6.67 °C Reset
If a 4 to 20mA signal is supplied, it is applied to Ter-
minals A+ and A- and jumper JP1 on the I/O board
must be installed between pin 1 and 2. To calculate the
chilled liquid setpoint for values between 4mA and 20
mA use the following formula:
Setpoint = Local Chilled Liquid Setpoint + °Reset
°Reset = (mA signal - 4) x (*Max Reset Value)
16
Example:
Local Chilled Liquid Setpoint = 45° (7.22 °C)
*Max Reset Value = 10 °F (5.56 °C)
Input Signal = 12 mA
(English)
°Reset = 8mA x 10 °F
16
Setpoint = 45 °F + 5 °F = 50 °F
(Metric)
°Reset = 8mA x 5.56 °C
16
Setpoint = 7.22 °C + 2.78 °C = 10.0 °C
= 5 °F Reset
= 2.78 °C Reset
A 240 to 24 Volt Ratio Transformer (T3)
is used to derive nominal 12 volt output
from the 120 volt supply.

York YLAA0170 Specifications

General

Brand	York
Model	YLAA0170
Category	Chiller
Language	English