70
Fig. 82 — C.TYP=4 (Tstat 2 Stg) Wiring
AHU
THERMOSTAT
(REQUIRED)
REMOTE ON/OFF
DEMAND
LIMIT SIGNAL
4-20 mA
SIGNAL
GENERATOR
DEMAND LIMIT STEP 2
DEMAND LIMIT STEP 1
38AP LVT
TERMINAL STRIP
–
+
FS1
25
24
18
16
14
13
8
7
6
5
4
3
2
1
ALM
R
15
12
Y2
Y1
R
X
C
G
W2
W1
CXB-J6
(38APD070-130 ONLY)
FIELD-SUPPLIED
TRANSFORMER
(REQUIRED)
RED
7
6
5
PNK
ORN
LLSV-A2
LLSV-B2
24 VAC
SECONDARY
LLSV-B (38APD)
LLSV-A2 (38APS)
or LLSV-B2 (065)
LLSV-A
or LLSV-B (065)
LEGEND
NOTES:
1. Field wiring must be in accordance with local codes.
2. LVT-1 and 2 are for the alarm relay. The maximum load allowed for the alarm relay
is 5 VA sealed, 10 VA at 24 VAC. Field power supply is not required.
3. LVT-24, 25, and 2 are for control of field-supplied liquid line solenoid valve (LLSV)
15 VA sealed, 30 VA inrush at 24 VAC. Field power supply is not required.
4. For 38APD070-130 units, an additional LLSV, 15 VA sealed, 30 VA inrush at 24
VAC can be connected to CXB. A field-supplied control transformer is required, not
to exceed 75 VA.
5. All discrete inputs are 24 VAC.
6. Installation of fan status switch (FS1) is recommended. If not used, a jumper must
be installed.
7. Energy management module (EMM) is required for Demand Limit functions, 4 to
20 mA, Demand Limit Step 1 and 2, or 4 to 20 mA Temperature Reset.
8. This control scheme is valid for 38APD,APS025, 027 and 030. It is not recom-
mended for units with more than 2 compressors, 38APD040-130 and 38APS040-
065.
9. This control scheme does not support digital compressor operation.
10. The contacts for Remote On-Off, Fan Status Switch and Demand Limit must be
rated for dry circuit applications capable of handling a 24 VAC load up to 50 mA.
AHU
—
Air-Handling Unit
ALM R
—
Alarm Relay
CXB
—
Compressor Expansion Board
FS1
—
Fan Status Switch
LLSV-A
—
Liquid Line Solenoid, Circuit A, First Stage
LLSV-A2
—
Liquid Line Solenoid, Circuit A, Second Stage
(38APS040,050, 38APD070-130 only)
LLSV-B
—
Liquid Line Solenoid, Circuit B, First Stage
(38APS065, 38APD only)
LLSV-B2
—
Liquid Line Solenoid, Circuit B, Second Stage
(38APS065, 38APD070-130 only)
LVT
—
Low Voltage Terminal
Factory Wiring
Field Wiring