York MAXE OPTIVIEW YK Service Instructions Manual page 122

Remote Setpoints
Setpoint (%) = 100 – [(3 –1) x 7]
= 100 – (2 x 7)
= 100 – 14
= 86%
RS-232
As shown in Fig.11, a setpoint can be received in se ri al
data form at Microboard J2 from the GPIC.
LEAVING CHILLED LIQUID TEMPERATURE
REMOTE LEAVING CHILLED LIQUID TEM-
PER A TURE SETPOINT with 0- 10VDC, 2-10VDC,
0-20mA, 4-20mA or Pulse Width Mod u la tion Sig nal
– Remote Leaving Chilled Liquid Temperature setpoint
reset can be accomplished by supplying (by others) a
0-10VDC, 2-10VDC, 0-20mA, 4-20mA or 1 to 11
sec ond Pulse Width Modulated (PWM) signal to the
OptiView Con trol Center. The LEAVING CHILLED
LIQ UID TEM PER A TURE setpoint is pro gram ma ble
over the range of 38°F to 70°F (water applications); 36°F
to 70°F (water ap pli ca tions with Smart Freeze protec-
tion en abled); or 10°F to 70°F (brine ap pli ca tions). The
Re mote input signal chang es the setpoint by creating an
offset above the lo cal ly programmed Leaving Chilled
Liquid Tem per a ture Base setpoint value. The setpoint
can be re mote ly changed over the range of 10 or 20°F (as
per the lo cal ly pro grammed REMOTE RESET TEM-
PER A TURE RANGE setpoint) above the Local Leav-
ing Chilled Liquid Tem per a ture Setpoint. For ex am ple,
if the Lo cal setpoint is 40°F and the REMOTE RE SET
TEM PER A TURE RANGE setpoint is pro grammed for
10°F, the Leaving Chilled Liquid Tem per a ture setpoint
can be remotely reset over the range of 40°F to 50°F.
The setpoint received through the COM 4B RS-232
serial port is not an offset that is applied to the locally
pro grammed BASE value as described above. Rath er,
it is an actual Setpoint value. The lo cal ly programmed
value is not used as a BASE in this application.
The OptiView Control Center must be confi gured ap pro -
pri ate ly to accept the desired signal type as follows:
• The appropriate Remote Mode must be selected:
AN A LOG Remote Mode must be selected when
using a voltage or current signal input. DIGITAL
Remote Mode must be selected when using a PWM
input.
122
• If ANALOG Remote Mode is selected, the RE-
MOTE ANALOG INPUT RANGE setpoint must
be set to "0-10VDC" or "2-10VDC" as detailed be-
low, regardless of whether the signal is a voltage or
current signal type.
• Microboard Program Jumper JP24 must be po si -
tioned appropriately per the input signal type as de-
tailed be low. It is recommended a qualifi ed Ser vice
Tech ni cian position this jumper.
IMPORTANT! - The signal type used
for Remote Leaving Chilled Liquid
Temperature setpoint re set and the
sig nal type used for Remote Current
Lim it setpoint re set must be the same.
For ex am ple, if a 0-10VDC signal is
being used for Re mote Current Limit
setpoint reset, then a 0-10VDC sig nal
must be used for Leaving Chilled Liq-
uid Tem per a ture reset.
0-10VDC
As shown in Fig. 12, connect input to Microboard J22-3
(sig nal) and J22-5 (Gnd). A 0VDC sig nal pro duc es a
0°F offset. A 10VDC signal pro duc es the max i mum
off set (10 or 20°F above the Local Setpoint val ue).
The setpoint is changed linearly be tween these ex-
tremes as the in put varies linearly over the range of
0VDC to 10VDC. This input will only be accepted
when AN A LOG Remote mode is selected, the RE-
MOTE AN A LOG INPUT RANGE setpoint is set for
"0-10VDC" and Microboard Program Jump er JP24 has
been re moved. Calculate the setpoint for var i ous inputs
as fol lows:
Offset (°F) = (VDC)(Remote Reset Temp Range)
Setpoint (°F) = Local Setpoint + Offset
For example, if the input is 5VDC and the Remote Re set
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 45°F
as follows:
Offset (°F) = 5 x 10
= 50
10
= 5°F
FORM 160.54-M1(503)
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YORK INTERNATIONAL