Transformer Wiring Requirements For Analog Economizers - Honeywell Design and Application Technical Reference Manual

Transformer Wiring Requirements for Analog Economizers

Economizer Panel Supplied With Same Transformer As Cooling Commercial Thermostat.
One of the most common misapplications of
economizers is related to the field wiring.
When the economizer will not open the
dampers and it is really cool outside, check
the wiring with the transformers. In analog
economizers relay coil 1S is used to open the
outside air dampers as the first stage of free
Economizer Panel Supplied With Separate Transformer From Cooling Commercial Thermostat.
24 Vac is supplied to the relay coil 1S in this
application from two separate transformers.
Though the first stage of cooling will switch
correctly through the economizer module
circuit, the relay coil 1S may not. Honeywell
ECONOMIZER LOGIC PANEL
W7459, W6210, W6215,
W7210, W7215, W7460
TR
1S SWITCHES
WHEN POWERED
BY 24 VOLTS
1S
1
1K
THIS SWITCH
ENERGIZES THE
1S1
MIXED AIR CIRCUIT
ECONOMIZER LOGIC PANEL
W7459, W6210, W6215,
W7210, W7215, W7460
TR
1S SWITCHES
WHEN POWERED
BY 24 VOLTS
1S
1
1K
THIS SWITCH
ENERGIZES THE
MIXED AIR CIRCUIT
1S1
39
Section 3 - Types of Analog Economizers
PRIMARY
VOLTAGE
TR1
CONTACT FOR
COOLING IN
COMMERCIAL
THERMOSTAT
2
RELAY COIL FOR
FIRST STAGE
OF COOLING
M13822A
cooling. To function properly 1S had to be
wired to both sides of the same transformer.
When the same transformer was used for
supplying the commercial thermostat, cooling
relay and the economizer logic module the
switching occured correctly.
PRIMARY
VOLTAGE
PRIMARY
VOLTAGE
TR1
CONTACT FOR
COOLING IN
COMMERCIAL
THERMOSTAT
2
RELAY COIL FOR
FIRST STAGE
OF COOLING
M13823A
recommends use of a single, larger
transformer for both the economizer logic
module and the cooling commercial
thermostat circuit.
Honeywell Economizers 63-8594-02