tekmar 155 Difference Setpoint Control - Manual

06/10
D 155
The Difference Setpoint Control 155 is a microprocessor-based control that allows the transfer of heat from a source
to a storage tank whenever the temperature difference between the two is greater than the selected ΔT setpoint.
Additional setpoints are also included to help prevent the storage tank from overheating or the source from freezing.
Both drainback and draindown systems can be used with this control.
Several displays provide a variety of useful information. The control can display the Maximum and Minimum
temperatures measured by both the Storage and Source sensors as well as the total heat transferred from the source
to the storage.
Difference Setpoint
Control 155
ΔT
Source
Storage Diff’l
Minimum
Maximum
ΔT • hours
PRGM
HEAT
F C
Item
Power: 24 V (ac) ± 10% 50/60 Hz 3 VA
5
Relay 2 Drainback l Draindown
6 3 4
Relay 1
No Power
7 8 9
Com Src Stor
1
2
2 1
C – R +
Power
Meets Class B:
Canadian ICES
FCC Part 15
Made in Canada
tektra 906-08
Sequence of Operation
Item selection
and display
button
Item
identifiers
Display for
temperatures
and setpoints
Programming
and display
buttons
Hole for mounting screw
°C or °F
indicators
Relay 2
operation
Hole for
mounting
screw
Wiring Chamber
and terminals
Programming
mode indicator
Relay 1
operation
Powering up the control
After the Difference Setpoint Control 155 is powered up,
the LCD segments are turned on for 3 seconds.
Δ
T Setpoint
The control measures the difference between the Source
and the Storage temperatures (ΔT). When this ΔT is
greater than the ΔT setpoint, Relay 1 is turned on to
transfer heat from the source to the storage. If the ΔT drops
below the ΔT setpoint less the ΔT differential, Relay 1 is
turned off.
Maximum Storage Setpoint
If the Storage temperature rises above the Maximum
Storage setting, Relay 1 is turned off. This relay remains off
until the Storage temperature drops below the Maximum
Storage setting less its differential.
Minimum Source Setpoint
If the Source temperature drops below the Minimum Source
setting, Relay 1 is turned off. This relay remains off until the
Source temperature rises above the Minimum Source
setting plus its differential.
Draindown
When the DIP switch is set to draindown, Relay 2 is closed until the Source temperature drops below the Minimum Source setting.
If Relay 2 is connected to a drain valve, the heat transfer fluid can be drained from the source when Relay 2 is opened. Once the
Source temperature rises above the Minimum Source setting plus the Minimum Source Differential, Relay 2 is closed and the control
continues with ΔT setpoint operation. See the Application Brochures A 155 for the correct wiring of Relay 2.
Drainback
If the DIP switch is set to drainback, Relay 2 is turned on (closed) for 3 minutes whenever Relay 1 is turned on. Relay 2 is typically
connected to a booster pump to overcome gravity head and prime a siphon.
Installation
Caution: Improper installation and operation of this control could result in damage to the equipment and possibly even
personal injury. It is your responsibility to ensure that this control is safely installed according to all applicable codes
and standards. This electronic control is not intended for use as a primary limit control. Other controls that are
intended and certified must be placed into the control circuit.
Step One Getting ready
Check the contents of this package. If any of the contents listed are missing or damaged, please refer to the Limited Warranty
and Product Return Procedure on the back of this brochure and contact your wholesaler or tekmar sales agent for assistance.
Type 155 includes: • One Difference Control 155 • One Universal Sensor 071, One Solar Sensor 085
• Data Brochures D 155, D 070, D 085, D 001
Other information available: • Essay E 001
Note: Carefully read the Sequence of Operation section in this brochure to ensure that you have chosen the proper control and understand
its functions within the operational requirements of your system.
Difference Setpoint Control 155
- Data Brochure
Diff'l
F
ΔT Source Storage
Minimum Maximum ΔT •hours
Difference Setpoint Control 155
Item
H11161E
Dat
e Code
24 V (dc) ± 10% 0.03A
Relay: 240 V (ac) 10 A 1/3hp
Signal wiring
must be rated
at least 300V
• Application Brochure A 155
No power
• New Solar Sensor 085 immersion type sensor included!