| Criterion
6.1.5.2 Control System Override
Criterion
text:
The
control subsystem shall include such provision for bypass, adjustment
or override controls as are required to facilitate installation,
startup, operation, shutdown and maintenance of the system. Safety
controls shall not have provision for bypass or override. All
switches and their function shall be labeled and easily accessible.
Comments:
Installers must use the controller that was specified
by the manufacturer for the particular SRCC certified system.
SRCC review has ensured that the control methods have the necessary
attributes to meet this standard. For example, differential controllers
have on/off settings that can be used during for both system operation
as well as service and troubleshooting. Photovoltaic and DC pump
combination systems are designed to incorporate an On/Off disconnect
switch. This switch must be incorporated in the installed system.
In addition to the system component requirements, informational
tags and labels that identify these components and their functions,
as well as explain their operational procedures must also be installed.
The SRCC approved manual that explains procedures must also be
provided to the client and be available at the system site for
reference and future service and troubleshooting.
The
differential controller shown in Figure 1 has the capability,
as shown in Figure 2 of being manually regulated. The On/Auto/Off
switch option in Figure 2 (within blue bold area) provides the
installer and system owner the ability to manually select the
controller's operational mode.
Figure 1
Figure 2
Another
differential controller model also provides the ability to control
the unit's operation (Figure 3).
Figure
3
Photovoltaic
controlled systems must also have some means to override the control
strategy. These systems must also incorporate an On/Off disconnect
switch.
The
disconnect device shown in Figure 4 below is not an SRCC accepted
disconnect switch since the two interconnecting wires have to
be separated manually. SRCC requires the use of a basic On/Off
switch.
Figure 4
A
simple and acceptable On/Off switch is shown in Figure 5. Note
that with this type of toggle switch the homeowner does not have
to disconnect any wiring connectors. On and Off operation is indicated
on the switch and in the event power has to be turned off to the
pump, the owner simply toggles the switch to the off position.
(Of course, the installer would construct some type of housing
to mount the switch.)
Figure
5
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