Taco SR501-EXP-4 User manual

POWER
ZONE 1
LED
INDICATORS
FUSE
6 AMP
FUSE
6 AMP
SR 501-EXP-4
POWER
CONTROLS
SLAVE
PRIORITY ON
RESET
PRIMARY PUMP ON
POST PURGE ON
PRIORITY PROTECT ON
PUMP EXERCISE ON
30 SEC/2 WK
MASTER
OFF
OFF
OFF
OFF
OFF
NORMAL
4 MIN/24 HOUR
ACCESSORY
PORT
120 VAC
INPUT
CIRCULATOR
HN/O NH
120 VAC
CIRCULATOR
PRIMARY
OUTPUT
N/C
INPUT
120 VAC
PRIMARY
CIRCULATOR
(OPTIONAL)
TO: "TT" on Boiler Aquastat
END
SWITCH
RESET
OVERRIDE
THERMOSTATEXPANSION
X W
R
X1A2CB
TO: DHW Aquastat if PC700
Boiler Reset is installed.
(See Page 2.)
T
24 VOLTS AC ONLY
C
SINGLE ZONE
EXPANDABLE SWITCHING RELAY
THERMOSTAT
See NOTE
NOTE: Resistor (1KΩ, 1⁄2W)
may be needed between
Wand Cterminals.
Operation: When the thermostat calls for heat, the circulating pump
is energized and the isolated end switch (X and X) will start the boiler.
Priority Operation: When the priority dip switch is set to ON and the
zone is actuated, all other connected zoning panels will stop operation
until the zone is satisfied. When the priority dip switch is set to OFF
and the zone is actuated, all other connected zoning panels will oper-
ate independently.
Mode Operation: When the mode dip switch is set to NORMAL, the end
switch relay will be energized if any zone is in operation. When the mode
dip switch is set to RESET, the end switch relay will only be energized
through the operation of a plug-in reset control or closure of Priority Input.
Primary Pump Operation: When the dip switch is set to OFF, the pri-
mary circulating pump output will not energize when zone calls for
heat. When the dip switch is set to ON, the primary circulating pump
output will energize when zone calls for heat.
Post Purge Operation: When the dip switch is set to ON, the circula-
tion pump output will stay energized for 2 minutes after its thermostat
or aquastat is satisfied, but not operate the boiler.
Priority Protection Operation: When the dip switch is set to ON and
the zone (priority) on master zone panel calls for heat continuously for
more than one hour, then power is returned to the space heating zones
allowing all the zones to function independently. Once the zone (pri-
ority) on master zone panel is satisfied, the control’s auto-reset is acti-
vated and the zone is again allowed to have priority for up to one hour.
Pump Exercise Operation: When the dip switch is set to ON, the solid
state timer cycles all the circulating pumps that are attached to the
Expandable Switching Relay at the selected time interval. The time
interval can be set for the pumps to run for either 30 seconds every 2
weeks or for 4 minutes every 24 hours.
End Switc : The switch closes when the thermostat calls for heat and
the mode switch is set to NORMAL. The end switch also closes when
the mode switch is set to RESET and a PC Series boiler reset power con-
trol is calling for heat.
Expansion Connections: Set the expansion switch to MASTER on the
switching relay that has the designated priority zone or is utilizing the
PC Series plug-in option. Set all other daisy chained controls to SLAVE.
Using thermostat wire (1 -22 gauge) connect between terminals A, B,
C on the master control to the corresponding A, B, C on the SLAVE
control(s). Controls may be daisy chained up to 20 zoning panels using
any combination of -EXP controls (120 zones if all are 6 zone panels).
T ermostat Input (24 vac):
RHot side of transformer. Connect to Ron thermostat.
WSwitched R signal from thermostat. Connect to W on thermostat.
CCommon side of transformer. Connect to COM on
thermostat (optional).
120 VAC Connections (N is Neutral, H is Hot):
Power Input Connect 120 Volt AC power.
Primary Primary Pump (optional)
N/O Zone Circulator Zone
N/C Zone Normally closed terminal for the Circulator Zone.
Will deactivate on a thermostat call.
NConnect to pump neutral leads.
WARNING: Wiring connections must be made in accordance with all applicable
electrical codes. Use copper wire only. 120 VAC wiring must have a minimum
temperature rating of 75°C. Failure to follow this instruction can result in person-
al injury or death and/or property damage. 12-1 gauge wire recommended for
120 VAC connections, 14-22 gauge wire for thermostat connections, and 14-22
gauge wire for 24 VAC source connections.
Wiring Diagram:
Instruction Sheet
SR501-EXP-4 Switching Relay
102-385
SUPERSEDES: March 1, 2013 EFFECTIVE: D c mb r 20, 2013
Plant ID# 9300-2872
SLAVE
ZONE PRIORITY ON
RESET
PRIMARY PUMP FUNCTION ON
POST PURGE ON
PRIORITY PROTECTION ON
PUMP EXERCISE ON
30 SEC/2 WK
MASTER
OFF
NORMAL
OFF
OFF
OFF
OFF
4 MIN/24 HOUR
Dip Switc Settings:
Specifications:
PRODUCT NUMBER INPUT MAXIMUM TYPE 1 ENCLOSURE
NUMBER OF ZONES VOLTAGE COMBINED LOAD WIDTH HEIGHT DEPTH
SR 01-EXP-4 1 120/60/1 VAC 12 amps 47/8"6
/8"2 3/8"
All circulator relay connections, including ZC/ZR, are rated 1/3hp (6 FLA, 36 LRA) at 120 VAC.
The end switch connection is rated 24 VAC, 1 amp.
The thermostat connection supplies a 24 VAC class 2 output.
This device complies with part 1 of the FCC Rules. Operation is subject to the fol-
lowing two conditions: (1) This device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
Troubles ooting:
• Problem: Digital thermostats do not work correctly when connected
to a switching relay.
• Solution: Some thermostats are a “Power Stealing” type which means
they are powered by the switching relay with just 2 wires (R& W). A
resistor may be needed in order to have the thermostat work properly.
This resistor should be placed between the W& C(common) termi-
nals of the switching relay. If the thermostat manufacturer does not
supply a resistor, a 1000 ohm ½ watt resistor has proven to work with
most models and is readily available at electronic supply outlets (e.g.
the batteries are fresh and installed correctly.
• Problem: No heat in a zone or room of building.
• Solution: LED diagnostic lights will help find a component that is
not working properly. The green LED should always be on, indicating
that power is connected and the solid-state fuse is good. When there
is a call for heat, the red LED will come on indicating power to the
zone circulator. This indicates the thermostat is working correctly. If
the red LED does not come on, then check the thermostat and ther-
mostat wiring for errors.
For information on Taco’s Switching Relays (SR)
including catalog sheet, instruction sheets, Visio
stencils and our highly praised Zone Controls
Wiring Guide, scan the QR code to the left or go
to our website: http://www.taco-hvac.com.

CONTROLS MADE EASY.®
TACO, INC., 1160 Cranston Str t, Cranston, RI 02920 T l phon : [phone] FAX: [phone].
TACO (Canada), Ltd., 8450 Lawson Road, Unit #3, Milton, Ontario L9T 0J8. T l phon : 905/564-9422. FAX: [phone].
Visit o r web site at: http://www.taco-hvac.com
Print d in USA
Copyright 2013
TACO, Inc.
Taco, Inc. will r pair or r plac without charg
(at th company’s option) any product or part
which is prov n d f ctiv und r normal us
within thr (3) y ars from th dat of start-up or
thr (3) y ars and six (6) months from dat of
shipm nt (which v r occurs first).
In ord r to obtain s rvic und r this warranty, it
is th r sponsibility of th purchas r to promptly
notify th local Taco stocking distributor or Taco
in writing and promptly d liv r th subj ct prod-
uct or part, d liv ry pr paid, to th stocking dis-
tributor. For assistanc on warranty r turns, th
purchas r may ith r contact th local Taco
stocking distributor or Taco. If th subj ct prod-
uct or part contains no d f ct as cov r d in this
warranty, th purchas r will b bill d for parts
and labor charg s in ff ct at tim of factory
xamination and r pair.
Any Taco product or part not install d or op rat-
d in conformity with Taco instructions or which
has b n subj ct to misus , misapplication, th
addition of p trol um-bas d fluids or c rtain
ch mical additiv s to th syst ms, or oth r
abus , will not b cov r d by this warranty.
If in doubt as to wh th r a particular substanc
is suitabl for us with a Taco product or part, or
for any application r strictions, consult th
applicabl Taco instruction sh ts or contact
Taco at [401-942-8000].
Taco r s rv s th right to provid r plac m nt
products and parts which ar substantially simi-
lar in d sign and functionally quival nt to th
d f ctiv product or part. Taco r s rv s th right
to mak chang s in d tails of d sign, construc-
tion, or arrang m nt of mat rials of its products
without notification.
TACO OFFERS THIS WARRANTY IN LIEU OF
ALL OTHER EXPRESS WARRANTIES. ANY
WARRANTY IMPLIED BY LAW INCLUDING
WARRANTIES OF MERCHANTABILITY OR FIT-
NESS IS IN EFFECT ONLY FOR THE DURATION
OF THE EXPRESS WARRANTY SET FORTH IN
THE FIRST PARAGRAPH ABOVE.
THE ABOVE WARRANTIES ARE IN LIEU OF ALL
OTHER WARRANTIES, EXPRESS OR STATU-
TORY, OR ANY OTHER WARRANTY OBLIGA-
TION ON THE PART OF TACO.
TACO WILL NOT BE LIABLE FOR ANY SPE-
CIAL, INCIDENTAL, INDIRECT OR CONSE-
QUENTIAL DAMAGES RESULTING FROM THE
USE OF ITS PRODUCTS OR ANY INCIDENTAL
COSTS OF REMOVING OR REPLACING
DEFECTIVE PRODUCTS.
This warranty giv s th purchas r sp cific
rights, and th purchas r may hav oth r rights
which vary from stat to stat . Som stat s do
not allow limitations on how long an impli d war-
ranty lasts or on th xclusion of incid ntal or
cons qu ntial damag s, so th s limitations or
xclusions may not apply to you.
LIMITED WARRANTY STATEMENT
120 VAC
INPUT
THERMOSTATS
BOILER
H
N
MASTER EXISTING
ZONE
CONTROL
T
TO: "TT" ON BOILER
AQUASTAT
AQUASTAT ON
DHW HEATER
A
Note: If Zone Control comes on without a call for heat,
reverse Reset Override input (1 & 2) wires on SR501-EXP.
ZONE
CONTROL
BOIL
SEN
OUT
SEN
BOILER SENSOR
OUTDOOR
SENSOR
PC700
JUMPER
DHW
HEATER
CIRCULATOR
CIRCULATOR
PRIMARY
CIRCULATOR
(OPTIONAL)
POWER
ZONE 1
LED
INDICATORS
FUSE
6 AMP
FUSE
6 AMP
SR 501-EXP-4
POWER
CONTROLS
SLAVE
PRIORITY ON
RESET
PRIMARY PUMP ON
POST PURGE ON
PRIORITY PROTECT ON
PUMP EXERCISE ON
30 SEC/2 WK
MASTER
OFF
OFF
OFF
OFF
OFF
NORMAL
4MIN/24 HOUR
ACCESSORY
PORT
H
N/O NH
120 VAC
CIRCULATOR
PRIMARY
OUTPUT
N/C
INPUT
120 VAC
END
SWITCH
RESET
OVERRIDE
THERMOSTATEXPANSION
X W
R
X1A 2CB
24 VOLTS AC ONLY
C
SINGLE ZONE
EXPANDABLE SWITCHING RELAY
FOUR ZONE SWITCHING RELAY
120 VAC CIRCULATORS
ZC
INPUT
120 VAC
ZONE 1 ZONE 2 ZONE 3 ZONE 4
ZONE1 ZONE2 ZONE3
SR 504-4
FUSE
6 AMP
FUSE
6AMP
FUSE
6AMP
FUSE
6 AMP
FUSE
6 AMP
XXRW
RWRW
RW
ISOLATED
END
SWITCH THERMOSTATS (24 VAC)
PRIORITY
120 VAC
ZR
HHNHNHNHNH NH
ZONE4
ZONE 2
POWER
ZONE 1
ZONE 3
ZONE 4
LED
INDICATORS
ZONE 4
PRIORITY
OFF
ON
PRIORITY
SR501-EXP and PC700 Boiler Reset Control Connected to an Existing Switc ing Relay
For additional wiring diagrams, see www.taco- vac.com.
Optional power stealing thermostat resistor part number: SRTR-001RP
(Value: 1000 Ohms, 1/2 watt or higher)
Replacement Switching Relay fuses part number: SR6A-001RP
(Manufacture: Littlefuse, Part Number: 229006)