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0-20mA - As shown in Fig. 19, connect input to Micro
Board J22-4 (signal) and J22-5 (Gnd). A 0mA signal
produces a 0°F offset. A 20mA signal produces the
maximum allowed offset (10 or 20°F above the local
setpoint value). The setpoint is changed linearly between
these extremes as the input varies over the range of 0-
20mA. This input will only be accepted when "Ana-
log" Remote Mode is selected, the "Remote Ana-
log Input Range" setpoint is set for "0-10VDC" and
Micro Board Program Jumper J24 has been placed on
pins 1 and 2. Calculate the setpoint for various inputs as
follows:
OFFSET (°F) = (MA)(REMOTE RESET TEMP RANGE)
SETPOINT(°F) = LOCAL SETPOINT + OFFSET
For example, if the input is 8mA, the Remote Reset
Temp Range Setpoint is programmed for 10°F and the
Local Leaving Chilled Liquid Temperature setpoint is
programmed for 40°F, the setpoint would be set to 44°F
as follows:
OFFSET(°F)
= (8)(10)
20
= 80
20
= 4°F
SETPOINT (°F)
= 40 + 4
= 44°F
4-20mA - As shown in Fig. 19, connect input to Micro
Board J22-4 (signal) and J22-5 (Gnd). A 4mA signal
produces a 0°F offset. A 20mA signal produces the
maximum allowed offset (10 or 20°F above the Local
setpoint Value). The setpoint is changed linearly between
these extremes as the input varies over the range of 0-
20mA. This input will only be accepted when "Ana-
log" Remote Mode is selected, the "Remote Ana-
log Input Range" setpoint is set for "2-10VDC" and
Micro Board Program Jumper JP24 has been placed on
pins 1 and 2. Calculate the setpoint for various inputs as
follows:
OFFSET(°F) = (MA – 4)(REMOTE TEMP. RESET RANGE)
SETPOINT(°F) = LOCAL SETPOINT + OFFSET
For example, if input is 8mA, and the Remote Reset
Temp Range setpoint is programmed for 10°F and the
Local Leaving Chilled Liquid Temperature setpoint is
programmed for 40°F, the setpoint would be set to 42.5°F
as follows:
YORK INTERNATIONAL
20
16
OFFSET(°F)
= (8 – 4)(10)
= (4)(10)
16
= 40
16
= 2.5°F
SETPOINT(°F)
= 40 + 2.5
= 42.5°F
FIG. 20 – REMOTE LEAVING CHILLED LIQUID
TEMPERATURE SETPOINT WITH PWM SIGNAL
PWM – The Pulse Width Modulation input is in the
form of a 1 to 11 second relay contact closure that ap-
plies 115VAC to the I/O Board TB4-19 for 1-11 sec-
onds. As shown in Fig. 20, connect dry closure relay
contacts between I/O Board TB4-19 (input) and TB4-1
(115VAC). A contact closure time (pulse width) of 1
second produces a 0°F offset. An 11 second closure
produces the maximum allowed offset (10 or 20°F above
the local setpoint value). 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 the Local setpoint
value. A closure 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:
OFFSET(°F) =
(PULSE WIDTH IN SECONDS)(REMOTE RESET TEMP. RANGE)
SETPOINT(°F) = LOCAL SETPOINT + OFFSET
For example, if the relay contacts close for 5 seconds
and the Remote Reset Temp Range setpoint is pro-
grammed for 10°F, and the Local Leaving Chilled Liq-
uid Temperature setpoint is programmed for 40°F, the
setpoint would be set to 44°F as follows:
FORM 160.55-PW7
16
LD04503
10
13
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