Tekmar 155 Data Brochure

- Data Brochure
Difference Setpoint Control 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 ∆T setpoint.
Additional setpoints are also included to help prevent the storage tank from overheating or the source from freezing.
F
Both drainback and draindown systems can be used with this control.
∆T
Minimum
Source Maximum
Diff'l ∆T •hours
Storage
Item
Several displays provide a variety of useful information. The control can display the Maximum and Minimum
Difference Setpoint
Control 155
temperatures measured by both the Storage and Source sensors as well as the total heat transferred from the source
to the storage.
Sequence of Operation
Powering up the control
After the Difference Setpoint Control 155 is powered up,
the LCD segments are turned on for 3 seconds.
∆
T Setpoint
The control measures the difference between the Source
and the Storage temperatures (∆T). When this ∆T is
greater than the ∆T setpoint, Relay 1 is turned on to
transfer heat from the source to the storage. If the ∆T drops
below the ∆T setpoint less the ∆T 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 ∆T 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:
Other information available:
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.
Programming
mode indicator
Item selection
Wiring Chamber
• One Difference Control 155 • Two Universal Sensors 071
• One Data Brochure D 155 • One Data Brochure D 001 • Application Brochures A 155
• Essay E 000, E 100
Hole for mounting screw
H11161
Date
Relay 1
S/N
operation
PRGM 1
2
Relay 2
operation
∆T
Source
Storage
Item
identifiers
Item
and display
button
1 2 3 4
Power
C – R +
Relay 1
and terminals
D 155
Power 24 V ac ±10% 2 VA,
30 V dc ±20% 0.03 A
Display for
Relays 120 V ac 10 A 1/3 hp,
temperatures
pilot duty 240 VA 2 A
and setpoints
°C or °F
F C
indicators
HEAT
Minimum
Maximum
∆T • hours
Diff'l
Programming
and display
Difference Setpoint
Control 155 buttons
No Power
7 8 9
5 6
Com Src Stor
Sen Sen
Sen
Relay 2
Hole for
mounting
screw
09/94